The Amp Garage

This is delving into hazardous testing, which you may not have done before, in which case imho you should work with a competent person to raise your experience. The commonly used technique is to insert a 1kΩ resistor in series with the filter cap and clipping a handheld multimeter across the resist...

rootz wrote: ↑Sat Apr 13, 2024 2:32 pm Here's the bastard son of the 005 and Odyssey power amp.

nice idea for EJ tone! any schematic or layout?

I’m working on a JCM-800 and I find that the bias voltage ranges from -58VDc to -42VDC. I have tried the EL-34’s that the amp came in with and a new set. I find with a new Marshall branded set if EL-34’s the maximum they will pull is 27mA. The bias circuit is incredibly simple. A diode, two resisto...

[Franchesca (Express "85") had Clarostat PC style pots throughout where both Ingrid (Express "92") and the Liverpool from Funks images have a mix of Clarostat, PEC and Mil-spec AB's but in similar layouts. The 1megs used for volume appear different than those used for treble etc. I would be interes...

[Franchesca (Express "85") had Clarostat PC style pots throughout where both Ingrid (Express "92") and the Liverpool from Funks images have a mix of Clarostat, PEC and Mil-spec AB's but in similar layouts. The 1megs used for volume appear different than those used for treble etc. I would be interes...

the problem is with the grill cloth

some 2204s had low voltages originally (around 370v)

This solution can be used on the screens together with an ordinary capacitor input on the plates but that requires two rectifiers

we need a new clip!

the speaker jacks should be grounded together with the phase inverter if you use negative feedback. correct, and it is the only truth.. people here using just random grounding for almost everything, or what they see from other people (the worst way), multiplying noise collected from the chassis dir...

When I lift R64 NFB resistor, the hum is almost gone. Did I miss a ground some where? OT secondary/speaker ground? Thats it... those damn speaker jacks got no connection to the chassis, even with lock washers. the speaker jacks should be grounded together with the phase inverter if you use negative...

impressive

no it works fine

this topic has been discussed a bit in connection with the 700v of music man amps. Often Winged = C= work, but these are not available anymore.

How about this PT: https://www.tube-town.net/ttstore/en/toroidal-273va-vh100r.html Pri: 230 V (blau-rot/blue-red) Sec 1: 330 V @ 0,5 A (rot-rot / red-red) Sec 2: 15 V @ 1,5 A (weiss-schwarz / white - black) Sec 3: 15 V @ 1,5 A ( schwarz - weiss ( black - white) Sec 4: 3,4 V @ 9 A ( blau - grau / blu...