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Pilot 240 Rebuild

B

brokenhalleluja

New Member
Hey guys.

This is my first post, and I am here on behalf of the gentleman who is rebuilding my grandfather's Pilot 240 for me. I aquired a schematic for it from sams, but there seem to be some peculiarities on this unit that do not match the schematic exactly.

Is anyone here familiar with this model amplifier? Please, any and everyone, pipe up. Any ideas for improvments?

If anyone has pointers but needs to see pictures of the chassis, I can easily provide pictures.

Great to find this place! I have a feeling I am going to learn a lot... maybe more than I originally intended!
 
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Welcome brokenhalleluja!

I have one of these amps that I restored the chassis on. I have yet to get to the faceplate and top cover. The 240 was probably one of Piolts sweetest integrated amps. about 12wpc, EL84 outputs.

As far as recomendations to restoration, Re-cap the entire chassis. Replace every coupling cap with auricaps or similar high quality film caps. replace the power supply filter caps as well. Antique Electronics Supply (tubesandmore.com) has the replacement 'all in one' filter cans, or you can just mount caps under the chassis.

Also replace the cathode resistors on the output tubes. THese tend to change value over time and will affect the bias voltage.

Pull the tubes, get some deoxit, and clean the tube sockets. Spray the socket and use the tube to clean it by insertying and removing the tube.

Other than that, there's not much else that can be done to these other than the physical restoration of the copper faceplate and covered top.
 
I have the 245 and love it. I had some of the major stuff that all these old tube units need done. Don't ask me what as I'm cluless, but it sounds stunning now.

Gary
245-AOn.jpg
 
Hello and welcome!

I am a newer member also,I have learned quite a bit of great info on this site,and I am sure you will too. I have a pilot 240 that I purchased at spring time in the Carolinas antique wireless meet a couple of years ago. I recapped it and cleaned the controls as described earlier,and replaced the output tubes with some really good sounding mullards.This amp sounds incredibly sweet! very crisp highs.It is a definite keeper.I have been using this amp in my workshop for 2 years with very little maintenence.The circuit is pretty straightforward,I am sure you wont have any problems getting it going.enjoy.Mike :music:
 
Response

I have owned two Pilot 240s. One had fixed bias for the each pair of final tubes and the other had pots that allowed bias adjustment of each pair of final tubes. Other than that, I saw no other differences. I sold both amps and have regretted that I did not at least keep one of them.

Bryan
 
sorry to give this thing a bump, but the gentleman working on my amplifier may be stopping by here to post, asking some more technical questions than I am capable of doing.

would you guys be adverse to getting *really* geeky with him about this thing?

thoughts? opinions?
 
I got a Pilot 240 and installed 2% Metal Film resistors and loaded it full of JJ tubes. This amp sounds awesome!!
 
Looking forward to rebuilding my 240. Just ordered caps, resistors, etc. It has all Sovtek tubes that are good so I'll leave them be.
 
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As far as the power resistor, its 10K ohms. It requires a 2 Watt, I believe I put in a larger wattage part in that position. I think it was 5 Watts. Apparently there were two versions of this amplifier. Mine has the 4 ohm tap from the transformer grounded to the chassis. The other version had 4 connections at the back for the output transformer (C,4,8,16) Mine has a curtain of sound set up that allows for a center channel. As far as the cap cans, I got the equivalent cans with a higher voltage from AES (www.tubesandmore.com) I bought two of the 40/40/40 @ 525 cans. When ordering the cans make sure that they will not be too large for the chassis cover. Another thing I noticed was that the bottom plate was a solid piece of aluminum with no vent holes. I perforated the bottom plate and it keeps things much cooler. The output tube sockets were in bad shape so I replaced them with Russian Military ceramic sockets. The amp sounds great and should last a long time.
 
Thanks for the quick and helpful reply. I have a 5 watt 10K ohm resistor to replace the "bubbled" one. I planned to wire E caps underneath but if I were to go with two 40/40/40 cans I would wire the two 40/40 uF together for the 80/40 uF can? Mine also has the center channel, the Pilot 240 Stereo Plus version.
 
brokenhalleluja said:
Hey guys.

This is my first post, and I am here on behalf of the gentleman who is rebuilding my grandfather's Pilot 240 for me. I aquired a schematic for it from sams, but there seem to be some peculiarities on this unit that do not match the schematic exactly.

Is anyone here familiar with this model amplifier? Please, any and everyone, pipe up. Any ideas for improvments?

If anyone has pointers but needs to see pictures of the chassis, I can easily provide pictures.

Great to find this place! I have a feeling I am going to learn a lot... maybe more than I originally intended!
Click to expand...

Here's what I did with the Pilot Integrated which turned out to be a tremendous improvement to the Integrated, Power supply was slightly modified for a substantial boost in dynamics as well.

There is enough gain to run the amp CD direct as well.

Don%27s%20Amp.jpg


SET12
 
I would go from the rectifier to a 40uf cap then through the 100 ohm 10W power resistor then the following cap should be two 40's combined. That is what my schematic is showing. You could put a 22uf capacitor in parallel with the 40/40 combo under the chassis to make the total 102uf. Which version do you have, the 4 ohm grounded version like I have?
 
I think I have the four connections at the back but I'm not 100% sure.
Second set of pictures are a little better.
 

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