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Messages - FixerUpper

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The Wurlitzer Electric Piano / Re: Replacing a 140 Amp with a 200A Amp
« on: March 19, 2013, 06:53:49 PM »
It was my mess up. One of the pins in a molex connector I used to link the 200A board to the existing connectors for the controls wasn't soldered very well. It really does sound great now with minimal hum. It was a lot of work but I'm glad I took on this project.

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The Wurlitzer Electric Piano / Re: Replacing a 140 Amp with a 200A Amp
« on: March 16, 2013, 12:19:39 PM »
I found a bad solder joint that fixed the volume and all the hum is gone. It turns out you can use a 200A amp in a 140 with the 140 transformer. It sounds great.

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The Wurlitzer Electric Piano / Re: Replacing a 140 Amp with a 200A Amp
« on: March 15, 2013, 11:52:54 PM »
I'm getting closer. I've gotten the reed voltage to about 145v and the hum has reduced significantly. I still cannot  get get low volume even with the pot turned all the way down. I think this needs to be the next thing to figure out. I checked a few voltages on the board and they are spot on.  I'm still plugging way.

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The Wurlitzer Electric Piano / Re: Replacing a 140 Amp with a 200A Amp
« on: March 13, 2013, 11:39:11 PM »
Mine was the 140 with the germanium transistors (for which no cross refference exists) and the varistors for the vibrato. From what I have read this was not considered a well designed amp. Also, I had given up on finding replacement varistors after trying a bunch. I have the 200a amp going (kind of) It still has a lot of hum so I need to go through and check my ground connections. Even with the hum it sounds great. I have to check a few other things too such as the lack of low volume. Right now it only plays loud. If there was anything redeeming about that old amp it is too late and there is no turning back now. It would have been nice to keep it all original but I think it was too late to keep it original a long time ago. This was a mess from rotted wood to keys that would barely move. Someone had even modded it with rubber bands around the keys to the whips to try and get it working better.  Now the action has been fixed, the case repaired and repainted. And an ebay 200A amp replacement. I would have loved to put a tube amp in here but you don't see those too often and they would cost a lot more than the $25 I paid for this amp.  I will still keep my eyes open for something more age appropriate in the future but I want to play this sooner rather than later and this seemed the the best solution.

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The Wurlitzer Electric Piano / Re: Replacing a 140 Amp with a 200A Amp
« on: March 13, 2013, 12:13:02 AM »
This is still a work in progress but getting there. The good news is that the 140 transformer works great with the 200A amp. I had to replace some of the resistors for the reed voltage with the ones from the 140 amp to lower the voltage from about 360 volts. Now it has 165 on the reed. I might adjust one more resistor to bring it down a little more. I'm getting +/- 21.5 for the rest of the circuit which it close enough. Mounting it on the old chassis was a bit of a hack but it seems good. It is a little more difficult to get it in and out of the piano but hopefully once it goes in it will stay in. Pics to come soon.

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The Wurlitzer Electric Piano / Re: Replacing a 140 Amp with a 200A Amp
« on: February 28, 2013, 12:02:11 AM »
So looking at the 200A schematic it needs +/- 22.5 volts. After replacing the selenium rectifier with silicon rectifier diodes it showed about 17 volts. When I hooked the wires to the board up I t went up to 21 volts. I think this is mainly due to the filter caps smoothing out the ripple. It seems like my existing transformer will be ok for the 200a amp. Any experts out there with an opinion?

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The Wurlitzer Electric Piano / Replacing a 140 Amp with a 200A Amp
« on: February 17, 2013, 05:52:33 PM »
As a solution to my Vibrato problem I am considering doing an amplifier substitution. Other than the logistics of fitting everthing together is there any reason this would not work? I'm not so worried about keeping everything original (obviously) because the 140 is not considered a great or unique sounding amp and I have already painted the case. I will have to investigate the transformer. Is there anything else I may be over looking?

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The Wurlitzer Electric Piano / Re: Vibrato problem on a 140 (Varistors)
« on: February 15, 2013, 11:28:21 PM »
Vibrato is not working now. I don't know if someting else went or if I was just imagining it working.

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The Wurlitzer Electric Piano / Re: 140 Restoration questions
« on: February 15, 2013, 11:18:58 PM »
I'm still working on my basket case 140. You can get a replacement bulb at Radio Shack. Be careful with the Varistors in the vibrato circuit. They are delicate and I still haven't found a replacement. I had some that I thought were working but they aren't now. I'm not sure if I just imagined them working. If you find something that works let me know. I'll do the same. The same goes for those germanium transistors.

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The Wurlitzer Electric Piano / Re: Vibrato problem on a 140 (Varistors)
« on: November 14, 2012, 11:05:02 PM »
in case anyone is interested the replacement varistors worked.

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The Wurlitzer Electric Piano / Re: Vibrato problem on a 140 (Varistors)
« on: November 13, 2012, 09:28:18 PM »
The 140 has a six pin plug on the back of the piano that is labeled as battery pack. On the schematic it is labeled "Battery Pack Tone Cabinet". I think it was for connecting some sort of external amplifier.

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The Wurlitzer Electric Piano / Re: Vibrato problem on a 140 (Varistors)
« on: November 12, 2012, 10:05:29 PM »
Well Morelock's got back to me and said they are sold out. I'm waiting for the ones from Mouser. I'm not too hopeful they will work but who knows I might get lucky.  If anyone has any tips for me on how to get this working it would be appreciated.

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The Wurlitzer Electric Piano / Vibrato problem on a 140 (Varistors)
« on: November 11, 2012, 12:45:54 PM »
OK. So I did something really stupid.  On the 140 they had this Amphenol plug the went from the power source to the battery pack which is just for the pilot light. I suppose it has some other purpose but I dont ever plan I using the battery pack (whatever that is). I thought I could get rid of the external wire and plug by hard wiring it under the chassis. To do this correctly I needed to wire a jumper from pin 6 of the battery pack plug to pin 2 of the 4 pin power plug. Unfortunately I had a bit of brain freeze and I wired it from pin 6 of the battery pack plug to pin 6 of the control plug. I suppose I was fixated on pin 6. Anyway, the problem is that pin 6 of the control plug goes to the vibrato pot. Now I have no vibrato but luckily everything else works. I have gone through everything and all the transistors still seem good and I'm still getting a reasonable signal to the base of transistor 5 which controls the varistors. Also, doing a basic diode test transistor 5 still seems good. But the emitter and collector of transistor 5 don't seem to be putting out a signal of any sort when checked with the oscilloscope. These both connect to varistors.

My question is, do you think the varistors could have blown even though everything else still tests out as good? I couldn't find any shorted caps or anything like that.

My second question is, somewhere on this form I found that the markings on replacement varistors from Morelock's is V14K / VEI 130. I typed V14K into Mouser and came up with this:

http://www.mouser.com/Search/ProductDetail.aspx?R=ETFV14K130E2virtualkey59250000virtualkey871-ETFV14K130E2

It is a combination varistor and fuse but it has connectors that allow you to ignore the fuse. I'm willing to give it a shot just to see if they will work (and dispell the belief that they are extremely rare if they do work) but would this just be a complete waste of time?

Any input would be appreciated. I attached the schematic for anyone interested. I also attached the manual which describes the vibrato circuit in the second paragraph on page 24 (according to adobe) or page 3 (according to what it says at the bottom of the page. but these are out of order)


One more question: The transistors in this are GT 2477. I can't find any information anywhere. Can someone recommend a replacement?

Even if no one responds, thanks for reading this far!

Jim

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The Wurlitzer Electric Piano / Re: leveling keys
« on: August 15, 2012, 12:51:15 AM »
Thanks. I'll be on it this weekend.

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The Wurlitzer Electric Piano / leveling keys
« on: August 13, 2012, 08:47:18 PM »
It seems like leveling the keys would be the first step in regulating. From what I have found the way to level the keys is with paper punchings under the balance rail felts. Is that correct? Are the paper punchings something special or can I make my own. I only need to raise a few keys a little bit.

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The Wurlitzer Electric Piano / Re: Setting Let-off Wurlitzer
« on: August 07, 2012, 10:11:33 PM »
Great tip Steveo. And perfect timing. I've got my electronics all done. I've lubed everything and now I am about to go through the process of adjusting everything. Your tip will come in handy.

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That's good news. Thanks again for the info.

Jim

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The Wurlitzer Electric Piano / Re: Diode direction
« on: June 26, 2012, 07:42:06 PM »
Now I see it. Thanks Brad.

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The Wurlitzer Electric Piano / Diode direction
« on: June 24, 2012, 11:18:19 PM »
I'm looking at the 200 series schematics from Vintage Vibe and it looks like the diodes 1 through 4 are shown in the wrong direction on PCB diagram of the 1973 version. The direction is reversed from the 1971 version which I think is correct. The schematic shows them in the same direction for both versions. Can any confirm this for me?

Also, the burn't out ones on my board are reversed fron the PCB diagram which either confirms my suspicion or might be the reason they burnt out.

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Looking at the manual it seems the amp for the 200 underwent a number of revisions. I was about to start rebuilding the amp but I realized I have the smaller transistors (Preamp,etc.) from the older version and the transistors that go on the heat sink from the newer version (i should say equivalents of the newer version). I was thinking that since the voltage measurements seem to be pretty much the same between the two versions that they just chose newer transistors that had the same characterisitics. In other words, that the transistors between the two versions are equivalent to each other even though they have different codes. Does anyone know if my logic is sound or am I overlooking something obvious? I'm calling the 1971 revision the old version and the 1973 revision the new version.

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The Wurlitzer Electric Piano / Re: To Buy Or Not to Buy
« on: June 19, 2012, 10:53:39 PM »
Is Wurlitzer even still in business? Vintage Vibe is making new versions of the Wurlitzer. Of course it is much more of a boutique thing than the Rhodes.

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The Wurlitzer Electric Piano / Vinyl dye video
« on: June 10, 2012, 12:10:18 PM »

I'm going to be restoring a piano soon and I want to restore the cover as part of the project. I haven't chosen a color yet and I may just go with black if I chicken out on something more colorful. I came across this video for a roll on dye. What do you think? I know it's a car but do you think the technique could be applied to a piano or am I overlooking something? It is not the most informative video but before this I have only seen spray on methods.


http://www.youtube.com/watch?feature=player_embedded&v=AN-WcgoW_AY

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The Wurlitzer Electric Piano / Re: Wood repair on 200 model
« on: June 08, 2012, 07:24:12 PM »
There are a lot of new products like bondo where you mix a hardener in to activate the curing of the paste but it is made for filling wood. Just go ask at any harware store.

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