Now it's time to ...

looks like some serious cleaning and detailing on those units before it is time to do much of anything. Enjoy getting intimate with your new amps.
 
I'm going to add a speaker protection module inside. Something compact that can be added elegantly.
 
amr2,
I've repaired and refurbished two P2200s, one had a intermittent popping sound after the repair. Traced the problem down to some counterfeit transistors (tested OK on the cheap transistor tester), see picture below. Both of my P2200s sound really good, they are my favorites. I didn't add speaker protection, but I did a couple of 2 amp inline fuses to my speaker cable, I hope it's enough protection. Looking forward to seeing what you do for speaker protection. counterfeit.jpg
 
counterfeits....:no: A couple of weeks ago I repaired an amplifier, somone tried to repair it before. And I found this:

BF245A, N-channel silicon field-effect transistor:

IMG_4842.JPG

About the protection, I already have the modules, one per channel. I'll put them next to the output connectors, reversibly and without modifying the chassis. I hope to upload some pics soon.
 
I'm also looking forward to seeing your protection circuit placement. I just recently got a P2201 (a P2200 without the meters) and have been wondering how to retrofit a DC protection/delay circuit in it.
 
I'm also looking forward to seeing your protection circuit placement. I just recently got a P2201 (a P2200 without the meters) and have been wondering how to retrofit a DC protection/delay circuit in it.
Good evening
I have a complete 22 page service manual for P2200 if that will help in your Yamaha project. I have 3 P-2200 I’m building a vintage system with
 
No, I’m going to use the BE lines (13 VAC)
Link to the modules I bought. Based on UPC1237 chip

http://s.aliexpress.com/ema2Mrqi
I saw that unit when I was looking, I think it'll work great. Do you know how much current it'll draw? Do you plan to use an inline fuse? I thought about using the BE lines, I was just a bit concerned about the current draw (should be small though, relay coil draws 77mA) and injecting noise into the amplification stage.
 
I have to check it, but I think the current draw should be low, less than 100mA, and noise shouldn’t be a problem.

I did not plan to use an inline fuse.
 
Installed my speaker protection boards yesterday, I ended up using BE (13V. AC) to power the modules. Here are some pictures of right side installation (left side was complete first).

Speaker Protection Board
View media item 15001
Locating the Board
View media item 15004
Mounting holes drilled and tapped
View media item 15003
Rubber insulator sheet
View media item 15005
Screws and spacers in place on board
View media item 15002
Board Mounted
View media item 15010
Board wired
View media item 15008
Board wired to speaker terminals, BE ac power, and right amplifier board
View media item 15009
Protection Board installed showing clearance to amp board
View media item 15006
View media item 15000
The P2200 works great with the protection board installed. No more turn-on pop, no more playing on after the unit is powered off, and lastly no more worry about excessive dc offset causing speaker damage. This board does not protect the amplifier from dead shorts across the speaker terminals.
 
Excelent work Barry! This is how I plan to place the modules.

BTW, what capacitors have you used to recap the boards? Panasonic FC?
 
Alberto,
Thanks, I used Panasonic FC's:
4 x P10352-ND EEU-FC1J471 CAP ALUM 470UF 20% 63V RADIAL
4 x P10301-ND EEU-FC1V471 CAP ALUM 470UF 20% 35V RADIAL​
Vishay axial:
2 x 4245PHBK-ND MAL213818221E3 CAP ALUM 220UF 20% 63V AXIAL​
EPCOS (TDK) Film:
2 x 495-5047-1-ND B32529C0474J189 CAP FILM 0.47UF 5% 63VDC RADIAL​
Nichicon Aluminum Poly:
2 x 493-3711-ND RR71A101MDN1 CAP ALUM POLY 100UF 20% 10V T/H​
I also replaced the common anode and common cathode diode arrays with these Schottky types:
2 x 1655-1098-ND MBRF10150CTR DIODE ARRAY SCHOTTKY 150V ITO220
2 x 1655-1097-ND MBRF10150CT DIODE ARRAY SCHOTTKY 150V ITO220​
I had 3 of 4 (D114 and D115) diode arrays fail on one of my P2200s. These SCHOTTKY diodes have the added benefit of a lower voltage drop to rectify BE, offsetting the voltage drop cause by the speaker protection boards!
Hope this helps with your project!
Barry
 
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