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Messages - sean

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1

Stevie,

Using a different wall wart to power this circuit will not fix your Li-ion battery charging problem.

I assume that the circuit was designed for an AC-AC wall wart transformer, not the 15V DC supply you are using.  However, if your 15V DC supply is working, then keep it.

The 15V DC input will probably make the power-on indicator red LED run hot and bright, but as long as that LED is okay with 50mA and the resistor doesn't burn up from the 0.675 Watts (it is rated for only 0.500 Watts), AND that the input voltage is high enough that the 78M15CT regulator doesn't go into cut out, well, you are fine.*

If this were my Dyno, I would swap the current limiting resistor that feeds the power-on red indicator LED with a 1KΩ 1/2-watt resistor (the LED should light up just fine with 13.6mA).


* The input voltage to the 78M15CT regulator is supposed to be two volts higher than the output.  The spec sheet lists the "Dropout Voltage" as 2.0V.  But if the circuit isn't sputtering and shutting off, then the regulator is working fine. 


Sean

2

Stevie,

I would not use this circuit with Lithium Ion batteries.

Assuming that the scribbled schematic is correct, it is a trickle charger.  It probably was expected to charge at less than 20mA, to keep it within the safe operating limits of the green charging indicator LED.

If you want to keep your Li-Ion batteries in the Dyno, you should disconnect the charging circuit (un-solder or clip one end of the 270Ω resistor that is next to the green LED).  This way, the Lithium-Ion batteries are never connected to the trickle charger.

Get an external charger that is designed specifically for Lithium Ion batteries.

Sean

3

The little collet?  I haven't seen a replacement part available.

I have search for "collet", "locking collar", "turreted grommet" - no luck. 

Try calling Chris and Fred at Vintage Vibe, and ask if they have one sitting in the junk drawer.

You could easily install a locking collar on top of the clutch, like a Rogers Memriloc. But you would have to adjust it with an allen wrench.
1/4" stop collar - https://www.mcmaster.com/6462K12

Sean

4


Stevie,

The 15V DC wall wart will never charge a stack of two 9V (or 8.4V)  batteries to full voltage.  You will probably never see the green charging LED light up. 

Maybe if you were able to discharge your batteries so that they were down to 6V each (remarkably dead), you might be able to get 5mA of charging current through the green LED, and it would dimly illuminate.  When the batteries charge up toward 6.8V each, the charging current would stop.  (This is because each diode in the current path drops about 0.7V.)  Your wall wart charging power source has to overcome the voltage drop in the rectifying diode, the voltage drop in the green charging indicator diode, and the voltage drop in the current limiting 270Ω resistor, and the internal resistance of both batteries.

This circuit was designed in the era of NiCd batteries. 

What batteries did you buy?  Did you also buy a charger designed for those batteries?

Sean

5



Have you checked that the potentiometer is not faulty?  Take it out of circuit and make sure that it doesn't become an open circuit at some point in the rotation.

Which Janus preamp do you have?  It should match one of these schematics:
Schematic for Janus preamp with sliders: http://www.fenderrhodes.com/org/ch11/fig11-1.jpg
Schematic for Janus preamp with sliders, version 2: http://www.fenderrhodes.com/pdf/late-mark1-suitcase-janus1.pdf
Schematic for Janus preamp with five knobs: http://www.fenderrhodes.com/pdf/late-mark2-suitcase.pdf


Sean


6




http://www.fenderrhodes.com/org/ch11/fig11-10.jpg

Are the diodes good and not backwards?  See CR3 and CR4 in schematic.
That pilot light is a little neon blub, right?

Have you looked at the AC voltage at the output of the power transformer?


7

Three Hundred and Seventy Eight?

Izzatta Typo?


Sean

8
Buying / Re: wtb leg bag
« on: May 11, 2020, 06:26:11 PM »

Wow.  I am very curious.  Are you actually going to try to use a 40-year-old vinyl leg bag?  The leg bag is more difficult to use than it is worth. and I doubt it would last.

Here is what I use to safely secure the legs in the lid compartment:  make a leg bag out of an old pair of denim jeans.  I just ran downstairs to find the bag I made....  Looks like I found an old pair of pants and sewed the legs shut at the bottom.  Then I cut the pair of jeans in half to separate the legs to make two separate bags.  I also found a bag that I made out of the sleeve of a button-down dress shirt.  I guess I made that for the sustain rod. 

The jeans are much easier to load the legs into, and you just fold over the top of the jeans.  You can wrap a rag around the top end of the legs if you are worried about them scratching each other. 

Sean

9

The guts of the piano lift right out as one piece.  See chapter three of the service manual...

See http://www.fenderrhodes.com/org/manual/ch3.html
and
https://ep-forum.com/smf/index.php?topic=10252.msg57142#msg57142


10
The Fender Rhodes Electric Piano / Re: New Tine, No Sustain
« on: May 09, 2020, 03:43:27 PM »

I think you should have another go at tightening the tine block onto the tonebar.

Put the tine block into a bench vise, and use a small block of wood in your hand to push against the tonebar to keep it from turning.  Turn the wrench with the other hand, and you will get a very tight tine that is aligned with the super-short tonebar.

Sean

11

The silver color pedals were a slightly different shape than the black pedals.
See https://ep-forum.com/smf/index.php?topic=5575.msg27566#msg27566

I swear that I have a photo of the two pedal styles sitting next to each other, but I can't find it.

Anyway, I would not be excited about the chemical strippers, but there are strippers specially-made for aluminum.  Airplanes get stripped for repainting.
I wonder how badly a sandblaster would damage the surface.  There is also the boiling water trick to remove paint.

If you sand the pedal, make sure that you use sandpaper that has never touched steel or iron.  Bits of iron will get lodged in the aluminum, and it looks dull and ugly.  You will probably get some amount of sandpaper grit lodged in the aluminum as well. 

The cast aluminum pedal will probably shine up really nicely with blue polishing rouge and a cotton buffing wheel.  It won't be a perfect mirror finish, but it will look great underfoot.

Sean

12
Oh!  A stage piano.  And a beauty at that!  Covered in crud, and damaged, but not for long.

Your Fender Rhodes Stage 73 piano was built in 1970, 1971, or 1972.

Get yourself two large tables to work on.  One table to hold the action, one table to hold parts and be your workbench.
Step one would be to clean it up.   Put the piano on a more sturdy support (saw horses are ideal), then get underneath it and remove the screws that hold the keyframe to the case.  See http://www.fenderrhodes.com/org/manual/ch3.html, specifically:



Then you can slide out the action and set it on a sturdy flat table to work on it.  If the keyframe doesn't want to come loose, it is because there are more screws holding it down.  (There may be more than the four shown in the diagram above.)

Be careful when you lift the action assembly, because it looks like your harp is not screwed down to the harp supports.  When you get the action removed from the piano case, you can strip off the tolex, remove the hardware, and start sanding.  You can use the surviving end panel as a template to make a replacement for the broken piano end.  (Do you still have the piece you broke off?)

Unscrew the name rail at each end, and set it aside, then carefully remove the keys, and clean them up.  Be careful not to dislodge the felts and paper punchings that are under the keys on the balance rail.  In your vintage of piano, the cheek blocks are screwed to the key frame from underneath. 


When you get to installing new hammer tips, see chapter 9: http://www.fenderrhodes.com/org/manual/ch9.html


Remove the ridge on the hammer head that is closest to the back of the piano.


Read the service manual a few times and watch a lot of vintage vibe videos, and you will be more comfortable.
Read the technotes at http://www.fenderrhodes.com/service/technotes.html
Especially, http://www.fenderrhodes.com/service/keybed.html and http://www.fenderrhodes.com/service/action-inspection.html

Sean

13

D.

Relax.  You will be all right.  We can help you through this.  Please post some photos.

Are you saying that you ripped the side off the piano top? Or did you rip one side off the amp cab?

Chapter 3 of the service manual will show you how to remove the action from the piano top. 
See http://www.fenderrhodes.com/org/manual/toc.html

You will probably have to get in there and screw and glue a new piece of 3/4" plywood.  Find a buddy that has a table saw, and a bunch of bar clamps, and he will get it done with you.  Make sure that it is rock solid, and then re-tolex it.

Show us a photo of the wire that you are worried about, and we will explain.

Sean

14

You don't need to lube the grommets at all.  So don't.  The wax that you find near the grommets and springs is a common woodworking trick: to drive screws into hard wood, rub the screw threads on a block of wax (or soap) and the screw will be easier to turn.

I didn't know that the square hammer tips were used with all-plastic hammers.  I thought that as soon as the half-wood hammers disappeared (around 1974?), so did the square hammer tips.  Square hammer tips on half-wood hammers is a really nice combination.  I haven't seen square hammer tips on all-plastic hammers.  I didn't know.  Thus my surprise.


Sean

15
Parts, Service, Maintenance & Repairs / Re: Accessory loop and Mark 2
« on: April 26, 2020, 01:19:36 PM »



Replace the upper jack. 

Over time, the tip spring gets bent just enough that it doesn't push hard enough against the shunt button, or the button gets enough corrosion on it to lose contact.

Forgive me for being too lazy to modify my drawing to make it Rhodes-specific, but please see:
https://ep-forum.com/smf/index.php?topic=9948.msg55373#msg55373

Switchcraft 12A:  http://www.switchcraft.com/Product.aspx?ID=2699

See the Rhodes configuration of the two jacks at upper left corner of:
5-pin Janus preamp - http://www.fenderrhodes.com/org/ch11/fig11-1.jpg
5-pin Janus amp cab - http://www.fenderrhodes.com/org/ch11/fig11-3.jpg
4-pin Peterson preamp - http://www.fenderrhodes.com/org/ch11/fig11-8.jpg

Sean

16

I am surprised that your 1976 Rhodes has square hammer tips.  In 1976?  Really?

The order in which you do the operations is not super-critical.  You can do them in the order that you receive the parts.  The order that you plan to follow is reasonable.

There is no reason to replace the springs when you do the grommet job.  You can clean the wax off them if you like, but unless they are ugly rusted, keep them.
You can do the grommet job and reset the timbre in an evening or two, and you will notice a huge change in the sound of the piano.  It really is satisfying.

Then you can remove the harp, and set it aside while you tackle the hammer tip and damper jobs - and you should remove the felts from the hammer cams.

I don't think I would want to snap 73 hammers out of the combs just to get the felts or hammer tips off them.  Removing the hammers risks breaking the comb or nubs, and would require removing the bridal straps.  If they are glued in, that's a pain.  If the bridal straps have a dab of glue on every damper, then I would unscrew the key frame, and slide the whole action out of the piano. 

You can leave the keys and all your punchings and felts in place if you just unscrew the action rail and harp supports.  Then you can flip the action upside down to get at the hammer cams.

See Hollywood actor Fred Willard removing the felts:  https://vimeo.com/214571859

Take the felts off, clean it up, flip it over and replace the hammer tips and damper felts, then re-attach it to the key frame.  Put it back in the piano case, and put the harp back on, and re-set the strike line, re-set the escapement, then re-set the strike line again, and repeat until you get it where you like it.

Sean


(Actually Fred Dileone, not Fred Willard.  Honest mistake.)

17

Sam.  We were trying to save you from that foolishness.  Don't waste the effort with something you will have to tear out and fix later.

The miracle mod expert, Ben bjammerz Bove, has laid it out years ago:
Quote
I highly recommend removing the felts from the hammers, and reinstalling or putting new ones on the key pedestal.  The problem is you have to make sure the bump lines up perfectly with the curviture of the hammer.  if it's off slightly, you can either get the felt falling in front of the bump and making the keys lock up from playing, or if it's too far back the hammers come to rest much higher than they should, and stay slammed up against the tines and stop the notes dead.  I have seen this about 3 times so far with "just the bump" mods.  Will link this to the big thread later.  Trust me it'll save you time actually, if you have to redo the mod over again versus you just pull the felts first.

(from https://ep-forum.com/smf/index.php?topic=7214.msg36624#msg36624)


Also, read every word of this thread (all three pages), https://ep-forum.com/smf/index.php?topic=4666.0



Sean


18

Sam,

I believe that the general consensus is that it is best to remove the felts from the hammer cams, and install new felts on the key pedestals with the bumps.

Sean

19
The Fender Rhodes Electric Piano / Re: 1982, the best year?
« on: March 30, 2020, 11:06:51 AM »

FB fan groups never lie.  1982 was indeed the best year for the Fender Rhodes.  Well, if and only if:
(a) you have a 1982 model and are talking about trying to sell it, or
(b) you are "high on crack" (a phrase that was popular in 1982).

The 1982 Rhodes would probably have plastic keys, so the action mechanism is very loud (clickety clackity pung pung thump bonk), because the back end of the keys smack the thin felt strip on the bottom of the case and bounce impressively.  The action is slower or less responsive than wooden key models (even if you move the balance rail to the forward position in the plastic key rhodes, which you absolutely should do).  The plastic balance rail pins are more likely to break during player abuse or mishap than metal balance rail pins.

I don't hate my plastic-key Rhodes, but it is not as well loved as my other models.


Anyway, the improvements that lead to the Mark II certainly showed up in the late seventies Mark I pianos.  The only real differences in the first Mark II models is the flat-top lid and the different aluminum extrusion for the name rail with a control panel mounted in it.  (Otherwise, my 1979 Mark I is identical to my 1981 Mark II.)

When they completely changed the guts with the introduction of the plastic keys and removed the keyframe, I think they still called it a Mark II to try to mask the huge design change.  Claiming that the move to plastic keys would be a significant optimization would be a difficult statement to defend.  Maybe the statement originated in some 1982 Rhodes advertising copy, which would satisfiy condition (a) above.

Sean





20
The Fender Rhodes Electric Piano / Re: Im lost restoring mark II 73
« on: March 22, 2020, 02:37:44 PM »

Hey David,

Your piano seems to have a white spacer UNDER your wooden strip on the harp support.  I haven't noticed that before.
Maybe your wooden strip will come off easily.

Sean

21
The Fender Rhodes Electric Piano / Re: Im lost restoring mark II 73
« on: March 22, 2020, 02:27:00 PM »

David,

You can remove the wood strip on the bass side and leave it on the treble side if that would fix your escapement problem. 

Try to measure what the exact escapement is on the bass keys.  That means you have to measure from the top of the hammer tip to the bootom of the tine surface when the key is depressed.  This is a really difficult thing to measure, because every part of the piano is in the way.  I use the tail end of my dial calipers to measure from the tip of the hammer to the top of the tine, and then subtract the thickness of the tine.  But it is a fiddly inexact-but-close-enough method:  it is hard to keep from pressing the tine down with the calipers, and hard to know when you are barely touching the hammer tip.  But three-digit accuracy is not required.

Another method is to cut an index card to create a feeler gauge; but instead of using the thickness of the card, use the width of the strip to measure.  Cut a half-inch wide strip of paper, and then either fold it or use a piece of tape as a handle.  Put the half-inch wide strip to extend below the tine, and push down the key.  If the hammer touches the paper, then you can cut the paper thinner and thinner until the hammer barely doesn't touch anymore.  Then measure the width of the paper, and that is your escapment measurement.

Both methods are fine when the tonebar is twisted, but the flat tonebars are inconveniently in the way.  So just measure the escapement at the bass end of the piano, and try to eyeball a guess at the treble end.

If the escapement at the bass end is close to 3/4", then you would almost certainly want to remove that wooden spacer from the top of the harp support.  It will be glued to the aluminum, so sometimes they are a bear to remove.  Some folks have said that it came off easily.  I don't know if anyone has tried using a clothes iron to heat the strip and soften the glue. 

If the escapement is less than 1/2" of an inch, you might remove the wooden strip, and then add cardboard (poster board, or a cut-up file folder) spacers on top of the aluminum harp support to get the escapement into your preferred range, and then fine tune with the screws at the end of the tonebars.

On the treble end, the escapement is remarkably close to zero by eye.  You have said that the treble notes are playable, so you may be able to leave the wood strip alone, or you could remove it, and build that side up with layers of paper as well.

Sean


22
The Fender Rhodes Electric Piano / Re: Im lost restoring mark II 73
« on: March 19, 2020, 06:10:33 PM »

It will be easier to understand once you get fiddling with it a little.

Before you mess with the shims, make a few experiments:

Pick a key where you believe that the hammer is striking the end of the damper.  Lower the tine down (tighten the screws so that the tonebar gets closer to the wooden harp) until the hammer can't swing high enough to whack the damper - it should stay clear of the damper the whole time.  If you get lucky, you will only have to lower the tine and tonebar a little bit (removing shims from the harp supports will do this lowering too).  If that works, then move the tonebar back up to where it was, and remove some harp support shims!

Now, occasionally there were Rhodes pianos that come out of the factory with the unlucky situation where you can't get this fixed without clipping off a mm or two off the damper spring arms, but that should be a last resort.  You could also try bending the damper arm so that it has a greater (to effectively shorten it), but this risks ruining your damper setting.  (You might have to re-adjust the dampers if you drastically change the escapement anyway.)

I don't like to bend the damper springs much at all... as soon as I start messing with it, I have trouble getting it back to where I started.
Yes, I agree that there is an overwhealming fiddly balance there, but you won't solve it until you start fiddling with it.

If there are a few shims on the harp supports, it is easy to unscrew the harp, pull out the shims, and try the difference.  Before you unscrew the harp, make marks on the harp and the harp supports so that you can find the exact position that you started from.  You might want to change the strike line, but you might not.


Sean

23
The Fender Rhodes Electric Piano / Re: Im lost restoring mark II 73
« on: March 19, 2020, 01:41:06 PM »

How can you be lost when you have come to the exact right place: the ep-fourm!

I will bet a nickel that all of your problems are related to escapement and shims on the harp supports.  It sounds to me that your escapement is set too high.

Take a look at the service manual http://www.fenderrhodes.com/org/manual/toc.html

Specifically, chapter 4 - Escapement:  http://www.fenderrhodes.com/org/manual/ch4.html#4-1

There is a technote too: http://www.fenderrhodes.com/service/escapement.html

Your piano probably has wood strips glued to the top of the aluminum harp supports.  There could be black paper shims on top of the wood strips.  You may have to remove the black paper shims or even the wood strip, but first, try to see if you can adjust the escapement sucessfully with the tonebar screws.  Ideally, you want the tonebar to be 3/8' or 9.5mm above the wooden harp surface. 

When you adjust the escapement screw, you also have to re-set the timbre screw, so that the tip of the tine remains in the ideal location near the tip of the pickup.  Read the service manual a few times, and play with a few tines, and you will get the hang of it.

You should also watch Chris Carroll talk about escapement: https://www.youtube.com/watch?v=hSvOh8oMIUw

Sean


Wow!  The Rhodes SuperSite has a new look!  http://www.fenderrhodes.com/service/manual.html

24
The Wurlitzer Electric Piano / Re: Lubricating Action on 200
« on: March 05, 2020, 02:10:06 AM »

You are talking about lubricating the action centers, right Cinnanon?

25
The Wurlitzer Electric Piano / Re: Introduction and Wurlitzer 270 Butterfly
« on: February 29, 2020, 05:05:51 PM »
Josh,

I can see why you are excited.  It looks adorable.

To work on the action, Steve O has taught us that you want to find a PTG-registered tech that is willing to work on the little Wurlitzer action. 
See https://portal.ptg.org/4dcgi/directory/rpt/person.html - it looks like you can look for tech's within 100 miles of 84322.
Is the action bad enough that it cannot be played?  Did you already fix the broken whip flange?

Are there some notes that are out of tune?  The tuning of the Wurly doesn't drift around with humidity and thermodynamics like an acoustic piano.  The tuning is set by the lump of lead on the end of the tines.  Changing and adjusting the tuning is a bit of tedious work (add or remove solder from the end of the reed, mount it ever so slightly differently, and tighten the screws consistently).  There are experts here on this forum that can help if you are willing to dive in yourself. 

Sean


P.S. - You can easily re-size photos in PC Paint - Ctrl-W should bring up the "Resize and Skew" dialog.

26

There is no reason to steer away from a VV restoration.  It is still a Rhodes will a whole lot of vintage charm and heritage.

I honestly think there is no way to decide until you have a Rhodes under your fingertips.  One may excite you, one may not.

However...

The VV restoration should have hammer tips that are only 12 years old.  They will be nice and soft and sound great.
The original black tolex Rhodes will have hard hammer tips that don't sound like Donald Fagen, but it might still sound pretty good.

The VV restoration will have new damper felts that do a great job.
The original black tolex Rhodes will have ancient damper felts, and may not do a great job stopping the tines.

The VV restoration will have 12-year-old grommets that are probably still fine, but a grommet job is an easy task, and you can do that in an afternoon.

In either case, both piano's can be restored to work exactly how you want them to.

If the gold tolex turns you off, there is little chance that you will get over this.  I would hate to have an instrument in my living room or studio that looks like it tastes bad.  You want to be drawn to the instrument and adore how it looks.

I guess Rhodes pianos are painfully rare in Oz.  They are pretty easy to find in the USA.   I can't fix that.

Sean

27
The Fender Rhodes Electric Piano / Re: Mrk 1 77 vs Mrk II 82
« on: February 26, 2020, 04:35:04 PM »

Does the Mark II from 1982 have plastic keys? 

The plastic keys came in black or white...  here is a photo of the black plastic keys:



Rhodes purists are legally prohibited from showing any love for these plastic key models.  The action is a little klunky, with a lot of clickety-clackity hammer bounce, but the audio output is 100% Rhodes smoothness.  If you have a plastic-key Rhodes, I highly recommend that you move the action rail to the forward position. 

I wouldn't pay much for a plastic-key Rhodes.  (I already have one.)

So, my recommendation is that you keep both Rhodes pianos.  If you are forced to part with one, you might feel less guilty about getting rid of the 1982.

Sean


P.S. - The plastic balance rail pins are easy to break (in shipment or setup - I don't have any worry about them during playing), but since VV sells new key pin sections, I don't worry so much.
https://www.vintagevibe.com/products/rhodes-mark-ii-plastic-key-pins

28


Pick your favorite electronics supplier, Mouser, Digikey, Arrow, Allied, Avnet, Farnell, Newark/Element14, whoever...

Take a look at anything like:
NKK   M2022ES1W01    https://www.digikey.com/product-detail/en/nkk-switches/M2022ES1W01/360-1832-ND/1006911

C&K  7201P3HZQE    https://www.digikey.com/product-detail/en/c-k/7201P3HZQE/CKN9732-ND/2055010

NCE  8C2012-Z    https://www.digikey.com/product-detail/en/nidec-copal-electronics/8C2012-Z/563-1665-ND/5086630

E-Switch  100DP1T6B11M1QEH    https://www.digikey.com/product-detail/en/e-switch/100DP1T6B11M1QEH/EG2408-ND/378877


Digikey's website does a good job on the photos of the switches, so it isn't too have to scan through them to find one with a paddle instead of the round baseball-bat.


Sean

29
Buying / Re: I need help choosing a digital piano
« on: February 15, 2020, 10:10:51 PM »
Oh no!  I found a new toy that I want to get my hands on:  StudioLogic Numa Compact 2x.  Not a hammer action, but nine drawbars!!  Loads of built-in sounds, live access to effects changes, super light, very interesting.  It has piano and electric piano sounds, but the drawbar organ must be investigated.  Seven hundred bucks makes it way cheaper than a Nord... I wonder what it plays like in person.

https://studiologic-music.com/products/numa_compact2x/

Now I am on a quest to find a StudioLogic dealer....

Sean

30



AAACK!  I got confused and I was focused on the other schematic.  Let me scratch my head and re-think my hunches.  Crud.  I think I have to edit my previous post about how to stop the oscillator.  (Because the switch is on the other side of R26.)

Give me a bit...

Sean

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