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Yeah, I don't know if there is anything close to a standard rate when it comes to wurlitzer tuning since it is sort of an obscure and specialized service, and on top of that it depends on the condition of the individual instrument in question.  Unless they are a big shop that does a *lot* of service, I would imagine most techs charge hourly, and maybe have set prices for certain typical services that require a known amount of labor, such as reed replacement.

In any case, since you seem to be so far from the nearest reputable tech, I encourage you to learn to tune the piano yourself.  You've already got your hands dirty with the action and the amp, may as well develop the confidence to repair anything in there, right?  It will save you a lot of headaches in the long run - when something goes out of tune you can just fix it!

I think tuning is substantially easier than action adjustments - the tuner will provide a quantitative reference with relative ease compared to setting lost motion, let off, aftertouch, etc (as well, these are parameters which may vary depending on the individual tastes of the player)

Focus on just one reed at first.  Review the service manual section on tuning a few times before you start.  It's not terribly complicated, but it requires a bit of artful concentration and patience, with a pinch of mechanical aptitude (which you seem to have).

Regarding easy ways to flatten a reed without solder, if the correction needed is relatively small, you can try loosening the reed screw and pushing the reed towards the pickup before re-tightening.  This effectively lengthens the reed by a small amount.

There is also a very fine tuning adjustment which can be made by adjusting the tightness of the reed screw.  This is possible because the reed screw washer is conical, and thus a spring which can exert a varying amount of clamping force.  There is a very limited amount of useful adjustment available - too loose and the reed will not sound properly, too tight and you run out of adjustment and risk breaking the screw.  The range of this adjustment is probably less than an eighth of a turn on the screw.

As Steve said, wax will also work in a pinch, such as right before/during a gig or when no tools are on hand.

Also I recommend removing reeds from the piano if you're going to file them.  I think you just risk getting filings in the pickup or damaging the pickup with file.  I have seen a number of wurlitzers with file scars on the pickups! Also, wipe the metal dust off the reed before you reinstall it

And make sure there is no dirt or corrosion on the mating surfaces of the screw, reed, and harp.  This will just rob you of tone and sustain by preventing good electrical continuity from the reed to ground.

If you unscrewed action parts (hammer or whip assemblies) from the main rail when you lubed the action centers, it's possible that some of the flies did not properly reseat in the catcher after reassembly.  This will jam the hammer upwards and prevent proper key motion.

You can correct that situation by gently lifting the hammer and pushing down on the jack felt (the little red square of felt at the base of the fly) with either your finger or a small tool so that the hammer can fall into the proper position.  If it is really stuck, don't force it - loosen the screws on the hammer flange and/or the whip flange to free up the stuck parts and reassemble with an extra bit of care.

Like Steve said, it's hard to tell because the amp is in the way but that's my guess.  Also, I agree that you shouldn't mess with the capstan screws (the little gold ones) until you've determined that there is a particular reason that they need adjustment.

Ah yes I had forgotten that dead-sounding reeds could be caused by insufficient connection to ground - if they do not make good contact then their signal will not be strong as that is a key part of the capacitive tone generation scheme.  I do think there is something to notion of reeds going dead that are not on the verge of breaking, though I don't have a clear idea as to the mechanism for such a condition.  I have had reeds go extremely flat before breaking, as is typical, but they didn't seem to lose much tone or sustain up until the final death blow.

But  I have swapped dead-sounding used reeds for new or NOS reeds and seen marked improvement in tone and sustain.  This after thoroughly cleaning the old reed and its interface with the harp to be sure there wasn't a poor ground connection.  (BTW one way to identify whether a replacement reed has already been in use is to check for a bright spot on the otherwise dark underside of the reed, which is a telltale sign of many hammer strikes.)

Interesting info about 140 vs 140B too Steve.  I would imagine that they were not made concurrently for very long as it seems unlikely they would have maintained tooling for both versions for an extended period of time.  More likely that they continued to assemble 140 pianos from parts on hand until stocks were depleted while ramping up 140B production, since the 140B was essentially an improved design in many aspects.

I should also add that the one example of a 146 I have personally encountered is based on a 140B and not a 140.  It has the exact same amp, even with the vibrato components present on the board (but lacking wiring or a pot to engage it), and a modified control section on the bass cheekblock for toggling the speaker on/off and selecting self/ensemble for headphone output.  Why it was not designated the 146B is beyond me.

Hi and welcome!

I am pretty familiar with 140Bs, not so much with the earlier 140, but I can attempt to address your questions.

"Dead" sounding reeds could be a number of things - sometimes reeds do just seem to turn into duds, and replacing them with a new or known good reed with no other adjustments will resolve the problem.  Other causes might be a reed screw which is insufficiently tightened (sometimes I find reeds which are loose either from vibration or perhaps hack attempts to tune the reed flat without resorting to adding solder), cracked reed screw washers, or sub-optimal strike point for that particular reed.

Non-functional vibrato could be a faulty connection somewhere, a bad pot, or more likely that the caps and resistors in the vibrato circuit have drifted in value far enough to prevent oscillation from occurring (could also be a fault with the transistor which drives the oscillator circuit).  I have found this last case to be the issue with many solid-state wurlitzers I have worked on (140 and 200 series) - replacing the caps and resistors with known good components of the proper spec usually results in marked vibrato improvement.  But it is worth checking the physical wiring and solder points beforehand, just in case it is something as simple as a bad connection.

Regarding the bulb, I am not sure about replacements.  I believe Ken Rich sells a neon bulb intended for 200-series pianos which may perhaps be workable.  I typically install a domed LED unit in 140B pianos that I restore since it removes a potential source AC hum from the control area and should last a very long time.  This requires a bit of knowledge about how to get a proper DC supply voltage for whatever LED you are using, but it is not terribly complicated stuff.

As far as I know, 140-series pianos came only in the butt-ugly schoolhouse tan/beige/whatever, in varying degrees of flecked-ness.  I have seen quite a few painted black [aftermarket] and they look pretty sharp.  It all depends on your tastes and how well the finish has worn.  I think some people have reported success using flecky rock-texture spraypaint to replicate the original finish.  I have a 140B that I am thinking of stripping and doing an oil finish, since I think they used a pretty decent veneer on the case wood.   In any case if the veneer turns out to be ugly it will get something other than butt-tastic beige.

I believe the 140 was made in 1962-65ish, not sure on exact dates.   Anyone have some concrete info out there?  The readily-available info out on the net seems inconsistent.  Pretty sure they stopped making the 120 around 1962 and I haven't seen a 140b which is older than 1965, but I may be misremembering this stuff and/or making things up.

here's a project 112 amp on the well-known auction website in case you have any interest in monkeying around with trying a different amp:

http://www.ebay.com/itm/Vintage-WURLITZER-Electronic-Piano-Tube-Amp-Amplifier-For-Restore-Model-112-/370688048116

(not my auction)

I you haven't tried a 3-prong cord that may help (really it should be done anyway for safety reasons).

If you want to try seeing what effect it would have without modifying your amp with a new socket, take a 3 prong cord, and at the end opposite the plug cap the hot and neutral leads with wirenuts, and install a ring terminal on the green (ground wire).  You can attach this ground wire to the amp chassis (at one of the mounting screws would be the easiest way to do it).

Then plug the 3-prong cord in to a properly grounded outlet (ideally the same outlet as the other, original power cord).  Because you've got the mains covered up and isolated, it should be safe to do this.  Just make sure the amp is off and everything is unplugged when installing the temporary ground connection on the amp, if there is stray voltage on the chassis it could arc when offered a path to ground.

If using a 3-prong seems to help with the hum, I'd recommend replacing the 2-prong cord with a 3-prong.  It would be wise to do so anyway for safety since there are high voltages in the amp, but in the past I have noticed at least of couple old tube models that produced less hum with the ground lifted (only through the internal speaker - the headphone/aux out was quieter with the ground in place).  They were operating in a more dangerous state but I knew to be very careful and only ever used a cheater plug to temporarily lift the ground, rather than permanently altering the cord or amp.

Electrolytic caps do tend to fail with age, yes.  Ceramic, not so much, although they are cheap so cost is not a factor in replacing them, just labor which may or may not make a difference.

One thing though, film type caps can go bad, even if they seem fine with a cap meter.  I think this is one of the reasons why vibrato circuits get weak or stop working (the others being resistor drift and failure or poor performance on behalf of whatever is driving it, be it a tube or transistor).

Film caps can also go microphonic as they age.  I recently overhauled a Pianet N preamp, the film caps would make noise if you tapped on them with a pencil.  New ones fixed that.

Ah, sometimes the volume pot can cause trouble - have you used a contact cleaner like De-Ox-Id or the like on the pots and jacks?  Is the volume knob very crackly when you adjust it?

For example, my roommate has a Fender 75 amp that recently started misbehaving.  The reverb stopped working and the amp generally sounded dull and noisy.  We thought it might be a bad tube or reverb tank, or something else deeper in the circuit even.

Before we decided to really start digging into it, I cleaned all the pots and the reverb and footswitch connections - it immediately sounded 100% better, with minimal effort.  Remember, the pots are part of the signal path so if the contacts are corroded or dirty then you're going to be inviting all sorts of problems.

I've also read here and there that volume pots on wurlies can be a source of hum, though there's never really a thorough explanation of why in any of the accounts I've seen - just that sometimes folks have replaced the pot and hum magically goes away.  Could be that the resistive element is worn out and leaking stray signal to the wiper??  Who knows...

One other question are you using a 2-prong or properly grounded 3-prong plug?  If 2-prong, does flipping the polarity help?  It's inconsistent, but sometimes I get more noise with a wurly with the ground in place and sometimes I get more noise with the ground lifted.  I think it also depends on the quality of the power coming out of the wall in your location.

Hmm, is the transformer noise like electric arcing, accompanied by any smell?  That could be bad - but you'd know pretty fast if it really crapped out because the fuse would probably blow.

If it is just a mechanical noise, check the transformer mounting.  The transformer on my 200 rattled like a small buzzer before I played around with the mounting, now it runs quietly (can't remember if I tightened it up or just nudged it around to keep it from acoustically coupling with the amp rail).  Every once in a while if I bump the transformer while doing other work on the piano, I can hear the same sound come back momentarily.  So it's worth checking for mechanical noise.

As far as measuring cap specs, sometimes a cap meter will tell you a cap is fine, but since the meter is testing capacitance with a very small voltage, it may not be telling you the truth about the cap's functionality (or lack thereof) at normal operating voltages.  Just sayin'.  But the fact that you have successfully run audio signal through the reed bar input is odd.

Have you measured DC voltages around the amp to compare them to the schematic?

Also, with the reed bar disconnected from the amp, what's the resistance between the tip and the sleeve of the pickup's RCA connector?  It should be completely open, as I'm pretty sure the pickup is supposed to be fully insulated from the harp.

This is long overdue, but I haven't been able to get around to replacing the reed screws on my 720 until recently.

I used the McMaster-Carr parts I mentioned in a previous post.  They have only been in the piano a short while, so this shouldn't be considered a long-term report, merely my initial observations regarding their suitability as generic replacements.

The screws are fine - the thread fit is perhaps a little tighter but not so extreme as to cause me worry about galling, seizing, other thread damage.

The spring washers are a little thinner than the original, but have more spring to them, so I noticed I was able to coax a wider range of fine-tuning from adjusting the tightness of the screw.  We'll see how the tuning holds up over time.

The main drawbacks of these washers is that they are not captive to the screw, so they won't necessarily stay on the screw when you have them off the harp.  Also, the hole in the washer is a little bigger than an original, so it floats on the screw a little more, which conceivably could make tuning a little trickier, depending on the nuances of your tuning process.

Taking this into account, and noting that Vintage Vibe is now selling reed screws for a dollar each instead of two dollars each, I'd recommend going with the originals or repros that VV is selling, even if you need to do a whole bunch.  The only reason I went this way to begin with was that I had to redo an entire harp's worth of reed screws and the generics were a third of the cost of Vintage Vibe's parts at that time.

Tonally, I notice no real difference between these and originals in good condition.  Unless there's tuning difficulties down the road, I will probably leave them as is due to the expense and time required to replace all the reed screws again and do a full tuning from scratch, but in the future I won't go this route assuming VV's (or other future suppliers') parts remain reasonably priced.

If I'm accurately interpreting what you've written, you have the amp and reed bar out of the piano on a bench for testing, yes?

If the reed bar is just sitting out on the bench with no shielding whatsoever, there's going to be a significant amount of hum when you connect the pickup to the amp, although you should also be able to hear a signal from the reeds mixed in with that.  Is that the case, or is there no signal from the reeds when you strike or pluck them (just hum)?

If there's no signal, check C3 - it looks to be the coupling cap between the pickup and everything downstream of there.  I would imagine a misbehaving cap or connection there would give you trouble. 

Assuming you have no shorts between the pickup and the reed bar/ground, something tells me the issue lies not with the reed bar but in the signal path between it and the amp, since you say you get a decent signal using the record player input, and especially since two different reed bars produce similar or the same results.

Yes, it is the lower of the two screws which are visible from the front of the piano, hanging down from the whip.  They look like little dome-headed carriage bolts.   Lowering this screw decreases lost motion, raising it increases lost motion.  If the fly is getting stuck in the catcher then you want to increase lost motion.

You can visually inspect for the at-rest gap between the fly and the hammer butt.  Also, gently pushing down on the key will let you feel how much lost motion there is before the hammer starts to rise.

Ideally you want to use a capstan wrench that is the appropriate size.  If you only have to do a couple adjustments, you could try turning them by hand after removing a few keys to give yourself some room.  Sometimes though (especially if they haven't been adjusted for a long time) they may be very difficult to budge with your fingers.

Honestly the proper tool is a capstan wrench but if extra care is taken you might be able to get away with using something else.  I generally discourage this but sometimes ya gotta do what ya gotta do, right?  Just make sure not to damage anything if you're using an improvised tool.

Really, the capstan wrench is not a very expensive tool and it will allow you to adjust the let-off screw as well.  It's a worthwhile investment if you have any interest at all in doing your own regulation.

Oh and another reason a hammer might get stuck is if there is not enough lost motion in the action (very small gap between the tip of the fly and the hammer butt). If that is the case, the fly tip can get stuck in the catcher and fail to return to the at-rest position after a strike.

Visual inspection of the action components will allow you to discern whether the issue is the previously-mentioned fly dislocation (forgive my invention of terminology), insufficient lost motion causing the fly to stick in the catcher, or some other problem (loose/misaligned parts, missing felt in the hammer butt, etc.)

Lost motion is adjusted by raising or lowering the lower capstan screw (on the whip in 200 models, on the key in 140 models).  Factory spec for the 200/200A calls for a 1/32 gap, but I like to set it closer if possible (just at the point of lost motion), as I feel it adds more sensitivity to the hammer throw.  Different models and different instruments will have different potential adjustment limits as they are all unique beasts at this point, IMO (especially the older ones).

If you removed the hammers/hammer flanges from the action rail to shrink and lube their centers, double-check the screws are tight enough.  There is a notch in all the action flanges to help keep them properly aligned to their mating part, so it'd be kind of unusual for a hammer to strike in a different spot unless something was amiss here.

If the hammer flanges are tight to the rail and you can find no other issues, you can change the strike point of an individual hammer by using a soldering iron to soften the glue that holds the hammer tip into the hammer butt.  When the glue is softened you can bend the tip forwards or backwards to adjust the strike point and thus the voicing of that particular note.

Also, regarding hammers not falling back down - when reassembling action parts after having removed them from the piano for whatever reason, sometimes the fly can fail to resituate itself in the notch in the hammer butt.  The jack spring could be pushing the fly backwards, jamming it up behind the hammer.  If that were the case you'd have to lift the hammer up and gently pull the fly forwards until it could reseat itself properly.  It might be helpful to remove the key while doing so.

BTW there's tons of great info in the 200 series service manual, which you should be able to download from a number of places for free, including Vintage Vibe's website.  They also have a lot of videos on Youtube covering a wide variety of repair procedures.

Yep, the inside of the case is painted with conductive paint (for shielding).  So that is a ground connection for the sustain mechanism and pedal.  (If ever happen to find that you're getting extra hum when you connect the sustain pedal, you might wanna check the continuity there, or wire up a more secure connection.)

That's good info - I have experimented with modifying tremolo circuits in other amps, like Wurlitzers, guitar tube amps, etc.  First I plan to replace the trem caps with stock values, just to see how it performs, then I can set into messing about with it if needed.

What I'd really like to improve is the intensity of the trem.  When the oscillator first fires up the bulb pulses on and off quite intensely, a very distinct tremolo effect, but then it settles down into something more subtle.  I'd like to have that really choppy sound on hand since it can be quite musical when called for, but maybe it will return when I replace the caps and check the resistors for drift.  I notice a definite improvement in Wurlitzers that I perform this maintenance on, and it is essentially the same kind of circuit.

Also good to know the keyshaft grounding helps with any type of sticky pad - I suspected since they are a whole array of ungrounded aluminum rods that they would increase hum somehow, being aligned over the pickups.  My pianet is already pretty noise-free, though I should be able to get the thing dead quiet with a cap job and the extra grounding.

Somehow I missed both these replies - must not have set any notifications for them.

Turns out the Jaymar went away with a roommate who moved out so this project is on the shelf until I get ahold of another suitable toy piano.  I'll keep your offer in mind though, Rob.  In the end I think I'd need 25 pickups since it is typically a 2-octave piano.

So, Steveo, what I'm calling the soundboard is actually just the piece of masonite/pressboard that is on the back of the Jaymar.  The metal rods (like big rhodes tines) which are the tone-producing element are mounted directly to this board so I consider it the soundboard, since they are acoustically coupled.

Finally got some time to install my new Ken Rich sticky pads for my Pianet N.  The old ones in my Pianet were totally trashed and disintegrated so I have nothing to compare them to, but they work great!  I did get a service message from KRS saying some of the pads may have excess silicone grease on them, which could accumulate on the reeds and flatten their pitch.  All that need be done in that case is wiping off the excess grease from the reeds and pads.

I can't compare the old tuning of this pianet with the way it is now, but some reeds seem to have gone slightly flat during initial use, as expected.

One thing that I think is interesting is that this piano now sounds different from many of the Pianet N examples that can be found on Youtube.  I attribute that to the difference in pad material - the KR pads vs. the Clavinet.com pads which I see on almost all refurbished Pianets out there (except for the ones with the DIY rebuilt pads).

There's a rubbery-squeaky-skronky kind of click to the attack and damping that you hear a lot and I think it has to do with the properties of the Clavinet.com all-silicone rubber pads (triboelectric charging) .  Not an entirely unpleasant variation on the pianet sound - actually it can be a cool timbral quality - but I understand it can be problematic, sometimes requiring a lot of fussing over the pad placement and the keyshaft alignment.

The N that I have now is somewhere between a Wurlitzer 140B and a 200A sound, maybe a bit brighter and more present/focused, with a slightly different attack quality due to the nature of the pads vs. hammers.

It sounds pretty good for now but I am going to replace all the electrolytics and the vibrato caps since they are past due.  It's also relatively quiet considering it's still got the 2-prong cord and original caps, but I think I will also do the keyshaft grounding procedure that Clavinet.com has demonstrated on Youtube.

I would also like to mention that since I am missing the footpedal with my Pianet, I had to put a jumper on pins 1 and 3 on the footpedal jack in order to get any sound out of it.  I think I read about this issue elsewhere but I wanted to state this here for the sake of others who get into these pianos.

The schematic reveals that the footpedal is basically a 250k volume pot where pin 1 is the wiper, pin 2 is ground, and pin 3 is the return path to the amp.  The 3-pin DIN jack on my piano is not a switching jack, so without the pedal there is no sound.  As a result, this makes it a very convenient place to wire in an external volume control.

Once I get further along with the electronics, I may put together an external control box with volume and tremolo rate and intensity controls (relocated from the internal trimmer pots).

Cool, good find, would you mind posting the manufacturer part number for those pins?

I live near a big electronic distributor and all the molex-type pins they have are of a different type.  I had to harvest some pins out of a beat-up 206 that I picked up for $10 (it was missing the harps, reeds and all the electronics.  Still good for action parts and random bits though)

I would leave the incandescent and LDR assembly intact unless you really want to monkey with vibrato quality.  I think a big part of the contour or character of the pulsation has to do with the way the bulb lights up and dims.  An LED could behave differently than an incandescent in this way, though how it did would depend on the particular diode and power supply.  If you want to mess around with it, try putting together a whole new assembly and set the old one aside in case you want to put it back in.

Also consider that maybe the LDR is most sensitive to a certain range of wavelengths, and going to an LED could alter the response characteristics in that way too.

I have to agree about the electrolytics too, I have a few 140B pianos around right now - the one I mentioned earlier needed the whole board rebuilt as it was having a bunch of electrical issues, but I have another one that is dead stock and it is louder and more aggressive/full-sounding.  I plan on keeping that one and mostly leaving it alone until I encounter problems.

One thing to consider is you could always just replace a few caps at a time, like just the vibrato caps, and keep the old ones around, intact and labeled so you could put them back in if you weren't happy with the new ones.   In my experience sometimes just rebuilding the vibrato section will really make a big difference in the intensity of the effect, and it's a cheap way to bring some life into an ailing piano.

Also, this is a whole other thought I had about the 140B vibrato circuit, but here goes -

Since the LDR/bulb assembly determines the rate, intensity and contour of the vibrato, one could possibly devise a different, more modern means of controlling the bulb, so you could have a tremendous range of frequency, wave shape, or even alternate/asymmetric wave patterns!

One could potentially get some pretty wild delay/echo or synthy sounds out of a 140b this way.

Looks like you've been digging pretty deep!

In a 140B, R5, R6 and R7 are the main resistors which govern the vibrato circuit.

I have had very good results replacing R6 with a 25k linear pot (wired as a variable resistor) in series with a 1.8k resistor.   R6 is the one that is closest to the foreground and furthest to the left in your photo, between the first two big brown/red caps.  (btw, unless the piano sounds really really great as is, I recommend replacing all the electrolytic caps on the board)

I also replaced R5 (18k) with a 22k resistor, it seemed to dial in the speed range for me.   The range and quality is almost as impressive as the expensive aftermarket vibrato mods.

I put the extra pot where the headphone jack was.  I also modded the wiring harness to accommodate the new wires, but you don't really have to go that far.  I was refurbishing the piano in question for the purpose of selling it, so I wanted it to be seamless.

You may have to play around with the specific component values, as the resistor-capacitor network here is somewhat finely tuned; it will stop functioning if you exceed certain limits.  I suggest playing around with different resistors and alligator clips to find the best choice for your tastes.

Also, regarding the blend (depth) pot, I think it is pretty typical for the effect to be quite subtle or non-existent until halfway up or more.  This is the case with all my wurlitzers and many tube guitar amps I have had as well.

I guess it seems to read that way, although I'm not sure.   I think they came out with the 200 amps first, maybe they just tacked on the option of buying a 200A amp when they became available, without really updating the description?

I guess you could check with vintage vibe just to be certain?

Got my new Ken Rich sticky pads in the mail recently.  I haven't have any time to install them yet but they look great.  I'm gonna be out of town for a while but when I get back this is on my list of things to do.  Will report my findings when I get around to it!

I haven't tried either, but I am pretty sure the 200 amp won't work with a 200A power transformer - the voltages are different so you'd fry something or it just wouldn't work properly.

It does appear that VV offers a 200A amp that is not the tube/variable vibrato type, for $225.

I also noticed Ken Rich is getting ready to offer a new Warneck Research amp for the 200A, maybe you could wait and see what that is all about before making a purchase.

Has anyone tried the new sticky pads from Ken Rich yet?  I've just acquired a Pianet N that I think will need to have all the pads replaced.  I've seen the clavinet.com pads and they look like a new take on the construction & chemical composition, vs. the Ken Rich pads which seem at first glance to be faithful  recreations of the original design.

My understanding is that the original design is flawed since the foam in the middle of the "sandwich" will degrade over time, so it seems the Ken Rich pads are at risk of eventual failure in the same manner.  But I have also read that the clavinet.com pads are tricky to dial in, with some folks having to do a lot of keyshaft adjusting, or even adding a different kind of grease to get them to work right and sound good.

Anyone got any experience with both, or a well-informed opinion they'd like to share?

Yikes that is a lot for a piano that has not been professionally gone over.  Although it is definitely one of the most desirable models, and it appears to be in nice cosmetic condition and is all complete.  But still I don't see how you could consider that a wise investment.

As an aside, that seller was extremely nice and provided me with photos of the fall cover latch hardware, even though I was not a bidder on the piano.  I put them up in another thread which I started regarding the making of reproduction latches.

I managed to contact an eBay seller who was offering a 145b complete with the fall cover and legs.  He was kind enough to send me some detailed photos of the latch hardware, which I'll be using as a reference to fabricate new latches for my 140B.  They are pretty much what I expected them to be, but it is good to have an original example from which to work.

When I have time, I'll put up some dimensioned drawings in DWG and PDF format so others can make them or have them made at a machine shop.

In the meantime, you can check out the images I received from the eBay seller.

Also, if there's room at the back end of the bolt (not the flower head end) to grab onto it with vise-grips, and still room to get an end wrench on the nut, you can try that method.

If you mangle the bolt threads up a little it's not too big a deal as the nut will probably chase them back into shape as you remove it.

A few seconds with a soldering pencil on the bolt probably won't damage the ABS top.  If the bolt was aluminum, or brass, it would conduct the heat through very quickly, but the steel will heat up slow enough that you ought to be able to loosen it up and get it out of there without too much fuss.

One thing you could do as a safeguard is put a wet cloth on the head of the bolt (the flower part). It will help keep that area cool and concentrate the heat in the part you are trying to loosen up.

Also, ABS is somewhat more resistant to solvents than other plastics, like acrylic for example.  On the other hand, because the plastic of the top is 30-40 years old, it may be a little more dry/brittle and apt to craze or melt from exposure to solvents.  In any case, I think heat is preferable to solvents for dealing with threadlocker.

If there is threadlocker (such as Loctite) on the bolts, careful application of heat can help loosen the bond (in the case of high-strength threadlocker, like red loctite, it might be the only easy way).

You could try touching a soldering pencil to the bolt/nut interface to apply the heat.

The ABS plastic that the flower heads sit on will melt easily, so if you go this route, be extra cautious.  Even just a little bit of heat will probably help loosen up the bond.

Sorry, I failed to notice that the 2-watters were web-only.  I live close to a huge electronics distributor that has walk-up counter service so I think I must have gotten my resistors there.

Note that in a 200/206, there is no 7.2v rail.  Obviously in a 200A/206A, the 7.2v supply is a better choice because you can just use a 1/4W resistor for the LED.

In a 200, there is a 15.5v supply, although I haven't tried tapping into that for the LED mod.  I basically copped my choice of supply voltage from the Vintage Vibe mod. 

Also, the 2W dissipation rating is there for headroom.  Actual dissipation is just a little over 1 watt.  I think that's fairly insignificant compared to the power consumption of the whole amp, and even less so if you're running into an external amplifier.

Good point Rob - that is an alternative solution if 2W resistors are unavailable.   Generally I lean towards fewer parts, but it will indeed work just fine, as component failure in this case is sort of unlikely (at least without some other major power supply issues as a primary cause). 

Radioshack does have 1.8k 2W resistors available:

http://www.radioshack.com/product/index.jsp?productId=12566174 $1.86 for a package of ten.

So, all from Radioshack (just as a common example, I don't specifically endorse shopping there):

$1.14 for an LED (probably cheaper if you can buy more than one somewhere else)
$1.69 for 2 LED holders
$1.86 for 10 resistors

That's $4.69 plus tax, maybe a little more for wire, solder, and shrink tube if you don't already have some bits laying around.  Cheap and easy, and a satisfying little bit of work.

I was thinking too, if someone took the time to make or source some replacement jewels in different colors of plastic, you could easily put in a white or other color LED.  Could be nice if you have a custom-painted Wurly and you want to put a little icing on the cake.

I have this crazy idea to electrify an old Jaymar toy piano.   I've seen people stick a transducer element on the soundboard, but I want to try a magnetic pickup system.  Different tone, and less feedback to deal with at higher volumes.

The tone generators in it are steel rods that are struck with a plastic hammer, so I think it will work with some creative pickup mounting.  There is room at the end of each rod for a pickup to be placed in much the same manner as you see on a Rhodes.

It's a 2-octave piano, so I would need 25 pickups all told.  That could get expensive, so I want to try just one first and see if it can generate a musical tone when amplified.  I would just use a guitar pickup as a test but I think the Rhodes pickup form-factor is ideal, being a single pole piece with an adjustable bracket for dialing in the response and voicing etc.

Anybody wanna huck me a single pickup for cheap so I can do some testing?  This will be the coolest Jaymar ever if it works out.

Yes, you've got it, just use whatever stable DC supply is handy and go from there.  I don't think the supply source matters too much as long as the LED is happy and you're not messing with the signal path.  Tapping into the pickup's DC supply would probably not be my first choice, for example.

There can be many causes of hum or buzz in a stock 200.  Some are relatively easy fixes - I usually find that a combination of several very basic repairs will lessen hum and noise a considerable degree, at least enough that anyone I'm working for will immediately notice the change when they get their piano back.

If you search around this forum and on YouTube, there is a lot of helpful information to be found.  Just to get you started, the main causes of hum are bad electrolytic capacitors (especially in the power supply), poor AC lead dress, AC from the neon pilot lamp interfering in the signal path near the volume and vibrato controls, poor grounding, unshielded pickups.

There will almost always be a little bit of ground loop hum from a stock 200 amp.  You can listen for this if you plug the Wurlitzer into the wall, connect the aux out to an amp's input with a 1/4" cable, and turn the amp on.  With the Wurly's power off, it's likely you'll still hear a bit of hum that will go away when you unplug the 1/4" cable from the amp (assuming your amp doesn't hum like crazy on its own too!)

I have no experience with any of the new-production replacement amps out there, so I can't speak for whether or not they exhibit ground loop hum as well.  Also, keep in mind that even if you drop in a new amp board, there's still going to be the above-noted issues with AC lead dress, neon bulb, pickup shielding, etc.  Again I approach hum removal as the cumulative result of addressing several different areas of the piano.

Well, remove the neon bulb and its leads.  Follow them back to the AC solder terminal strip and cut them off.

You can use one of these to hold your new pilot lamp:



Radioshack $1.69 for a pack of two: http://www.radioshack.com/product/index.jsp?productId=2062559#

Drill a 5/16" hole where the old neon bulb was glued in.  There should already be a small hole there to get you started.  Then you can install the LED holder nice and tight, and in exactly the right place.  The legs of the LED will slip into the little rubber piece that fits in the back of the holder.

You need to solder in a current-limiting resistor in series with your LED of choice, the resistance value and dissipation rating of which is determined by the specs of your particular LED and the supply voltage you are using.

Here's a handy LED calculator for this exact purpose: http://led.linear1.org/1led.wiz

In a 200, I typically wire the positive leg of indicator LED to the 44V supply at the positive end of C6 (the big 1000mF one all the way on the right side of the board) or the nearby diode that is at the same junction.  The negative side of the LED can go to any convenient ground point.

So, in this example the supply voltage is 44V, the LED forward voltage is 2V, and the forward current is 25mA.  Plug it all into the calculator and you will see you need a 1.8 kOhm, 2W resistor in series with your chosen LED. (there is an actual formula you can learn for this, if you want to do all the math yourself.  It's not very complicated but the calculator simplifies things for those who don't want to get into the math)

A 2kOhm resistor would also work fine if it's easier to acquire.  The wattage rating is important as it is dissipating the excess current.  If you put a 1/4W resistor in there it's going to fry.

For the AC lead dress cleanup, the VV vid is here: http://www.youtube.com/watch?v=XhXUD01mSyQ

In part 2, they detail the LED installation and a few other things.

Great vid, that is helpful, just being able to see the state of your piano's guts.

First off - the hum you are hearing through the amp with the Wurly power off is probably ground loop hum.  It is there on just about every 200 series I've ever worked on.  If it disappears when you disconnect the 1/4" cable from the amp [edit: or unplug the Wurly power cable from the wall], that is a sure sign.   Usually it is minimal enough to be unnoticeable in live use.  There are ways to deal with it if it is really bothersome, but I personally don't think it's too big a deal.

Second - looks like you've got the original electrolytic filter caps in there (the big blue ones).  Those are likely culprits for at least some of the hum you are hearing.

Third - you've got a neon pilot lamp and your AC leads (the long black ones that go along the back of the chassis rail to the transformer) are poorly dressed - this is typical of what I've seen stock from the factory.  Vintage Vibe has a nice video about how to deal with this.  Basically you unhook those leads from the solder terminal strip on the left side of the chassis, loosely twist them around one another, then tape them down to the back side of the chassis rail with conductive foil tape.  The neon lamp can be replaced with an LED.  VV sells a kit but you can do it yourself for about $5 in Radioshack parts.

Fourth - does some of the hum go away if you unhook the RCA cable that comes from the harp output?  If so, you've got some hum coming from the pickups.  Adding the first-stage hum shields (200A style) under the dampers will really help quiet that kind of hum down.  They're available as a retrofit from VV and Ken Rich, and possibly others.

Have you tried Simichrome or the Novus polishing products?  Haven't tried either on black keys but I use Novus for lots of other plastic polishing applications.  I am only familiar with Simichrome as a metal polish (it is awesome for chrome and aluminum) but some folks have reported success using it on plastic as well.

What I meant is if you need to replace a great many reed screws, buying a few bags of parts from McMaster (or other industrial suppliers) at less than half of retail seems the way to go.   But for a few here and there, it's cheaper to just buy originals or the accurate reproductions.

Really the only differences I can imagine between the generics and the repros/originals would be the spring force of the washer and the conductivity of SS vs. Nickle-plated. (still not clear to me whether the originals or repros are nickle or SS, though).  It's probably an inconsequential difference as SS is used in a lot of electrical fastener applications, at least in my professional fabrication experience.  And certainly better in that regard than the corroded old-style flat-top screws in my 720.

As for the washers, I'll just have to compare the spring force through direct experience since there is no data on the original washers that I know of.

Anyway, I think the generics would look alright - only lacking the recessed top and mysterious "R".  I should note too, in my older Wurlitzers all the screws have flat tops.  So long as the damper arms don't bump into the screws while at rest, there shouldn't be any problems.

Besides, you can't see the reed screws from the audience, right? (sorry, begging the question, I know we all like to have our pianos looking top-notch under the hood, myself included ;-)

I'm going to order some replacements this week anyway as I need 35-50 new washers at least, but I will probably just do them all so they match.  And I'm not planning on spending $140 on a new set of screws.

I'd agree the conical washers do contribute to the ability to fine tune but I consider their locking qualities to be equally important.  I work in a fabrication shop that sends products all over the world, via any type of shipping you could imagine.  We use locking washers or nuts wherever possible, and loc-tite elsewhere.  We started doing this after we arrived at a big install in Germany where the products had arrived by rail and a great many screws had rattled loose in transit.

Also, I think if one needed only a few reed screws, using originals or VV replacements would be ideal so as to match the existing screws, but I find myself in a situation where the majority of the screws need to be replaced (or at least the washers).

My friend used to use one in his band when they had a keyboardist who was very particular about having something that felt like playing a real piano.  They are heavy but have a great sound, almost rhodes-like, but closer to a real piano.  Though I think I've only ever seen them go for $200-300.  I think the lower price is due to their lesser-known status, size, and weight, at least compared to rhodes/wurlitzer/etc.

[92314A242]

Bit of a Zombie Post but I thought I'd contribute another substitution from McMaster-Carr:

92314A242 - 18-8 Stainless Steel Hex Head Machine Screw 10-24 Thread, 1/2" Length, packs of 50 ($9.22 per pkg. as of this posting)

This is a better choice for the screw as it doesn't have an attached washer, which adds height to the screw head without the advantages of a free-floating washer.  (It is also non-slotted, to keep people from mucking about in there with a screwdriver when the appropriate tool is a nut driver! One slip with the screwdriver and you have yourself a broken hammer, etc.)

91235A109 - Nonserrated Belleville Washer 17-7 PH SS, NO. 10 Screw Sz, .47" OD, .04" Thick, packs of 25 ($8.27 per pkg. as of this posting)

The original screws (and VV's replacements, I believe) are not flat washers but are actually conical (known as belleville washers).  This makes them springy which helps to lock them in place and prevents them from vibrating loose.

For a set of 100, it would be $51.52 plus shipping and tax where applicable.  So around 60 cents per each reed screw.

Also, I think it's possible that the original screws and VV's relplacements could be nickle-plated steel.  Those would be stronger than 18-8 stainless, while retaining corrosion resistance and conductivity.  You have to be careful with 18-8 fasteners, they will strip, gall, and/or break more easily than plain steel.  But I think they are still an appropriate replacement if care is exercised in working with them.

[Note I haven't tried these yet but I am going to order some next week as I just picked up a 720 recently and about half of the washers are cracked.  I'll confirm them as appropriate substitutions when I get them installed, probably next weekend.]

If you do have a set to spare I could use them.  If you happen to have an extra "vibrato" knob too, that would be very cool.

Also, anyone out there have some fall cover hardware they can photograph for me?

I did some thinking about what it would need to be.  From a functional standpoint it's quite simple, most likely just a pin, spring, and a thumbscrew which threads into the side of the pin and acts as a stop for one end of the spring (the other end being trapped by the bracket on the fall cover.)

I am pretty sure I can make some from scratch without a reference, though a photo would help me get the appearance closer to the originals.

You could try the 100k/15k/5uf but in my experience I had to modify that arrangement to get a hot enough signal for my liking anyway.  That was the early arrangement from the factory, and later they switched to the 2.2k/6.8k - presumably to bump up the signal level?  Low aux output is apparently a pretty common issue with the 200 series, but easy enough to fix.

You could try reversing the positions of the 6.8k and 2.2k resistors, as suggested in the service notes.

Or you can add another resistor in parallel with the 6.8k to lower the total resistance.  If you have a couple alligator clip test leads, you can easily try different values in the circuit first before doing your soldering.

Hmm, well check that the pot works, but otherwise it sounds like there are some bad or missing parts in the vibrato circuit.

TR-4 is the driver for the vibrato oscillator, that could have gone bad.

Other parts to check are C46, C53, R54 and D6, these couple the vibrato signal to the piano signal.

Further upstream, C27, C38, C44, and R32, R33, R43 form the rest of oscillator circuit.  C39 controls the AC gain of the vibrato signal.  This is also the cap to play around with if you do get the vibrato working and it is "thumpy".  If any of these parts have drifted far from spec it may cause the vibrato to stop working.

btw, the .12uf caps in the vibrato circuit can be sort of hard to find.  I tried putting .1 caps in when I rebuilt my amp and they caused the vibrato to stop working.  I could have probably played around with changing the values of the resistors in the circuit to get it in tune again, but the simplest solution was to hunt down the proper caps.  I found em on eBay - same seller still has a bunch: http://www.ebay.com/itm/370378550191

Good luck!

Are you certain you removed the jumper between point 12 and ground?  It might be on the back of the board; I have never converted a 206 so I don't know which side it is typically on.

A video could be helpful, or just some photos and sound clips.  There might be any number of things wrong with your piano which will give you headaches, some compounding or obscuring other problems.  For instance, the vibrato section of your amp may not even be functioning properly because of bad or missing components, and nothing you do with regard to the pot wiring will change that.

On a stock 206, there would be a jumper between point 12 and ground, have you removed that?  It shunts the vibrato signal to ground.

If so are you sure all the other necessary components for the vibrato are on the board?

Which resistor is connected to ground, the 2.2k or the 6.8k?  The suggested arrangement is having the 2.2k connected to ground (6.8k would be connected the the jumper installed at the edge of the board, and the common junction of the two resistors is where your aux out signal lead is connected).

If this is how you have it, you can attenuate the signal by putting a larger-value resistor in place of the 6.8k, or adding another in series with it to increase the overall resistance.  You can play around with the resistor values until you get the signal level you desire.

Also, do check the trimmer pot that is on the PCB.  That controls the preamp gain.  If it's turned way up that may also be heating up the signal. 

As far as connecting the trem pot goes, the wiper (center lug) goes to point 12, one outer leg goes to point 13, and the other leg goes to ground.  (refer to the PCB layout in the service manual for these locations on the board)

If the pot works in the reverse as is desired (clockwise turns off the trem), reverse the two outer leads.

Awesome!

Remember, there are a number of relatively easy things you can do with the 200 to cut down on hum before getting into the amplifier itself:

- 200A-style reed bar shields (huge improvement in RF hum reduction)
-  improved lead dress and shielding of the AC mains going to the transformer
- replacement of the neon pilot light with a DC-supplied LED - VV sells a kit but if you are savvy, all the parts are available elsewhere for under $5
- check all grounds for good conductivity, especially the RCA connection from the reed bar.