1960 Tremolux questions and advice needed

[baritone61]

Hey all, I'm a long time lurker who has just picked up an unusual(?) big box 1960 Tremolux.
I have a fair amount of experience with blackface/silverface fenders but this is my first tweed amp. I'm still learning tube amps and this is proving a bit tricky for me

1)I can't find a matching schematic. It seems close to a 5G9 but not exactly.
-Amp dates to 1960 from serial number.
-Label says 5E9-A with 5U4GA-6V6GT-6V6GT-12AX7-12AX7-12AY7
-transformers are 8160 125C1A 125A1A

2)the wiring for the 6V6s doesn't match anything I've seen, it has 1.5K 1/2watt resistors across pins 5+6.

When I got the amp it was missing the rectifier and power tubes.
-Filter caps had leaked so I replaced those.
-Replaced the rectifier and power tubes.
-I brought it up slowly on a variac and it didn't seem to be drawing too much current but after a couple of minutes it blew the fuse.
-B+ and bias were in the ballpark but I didn't get reading on each tube before the fuse went.
-powered it up with no tubes and the fuse went right away.
-Now I have it set up with a series lightbulb tester which is lighting up with no tubes installed.

Doesn't seem good, am I missing something obvious here?


[img:800:447]http://i.imgur.com/SeXTfbw.jpg[/img]
[img:800:600]http://i.imgur.com/G98mhMV.jpg[/img]
[img:800:600]http://i.imgur.com/ZhvEwZJ.jpg[/img]
[img:800:600]http://i.imgur.com/VnEEYtA.jpg[/img]

[martin manning]

Isolate the power transformer and see if you can get it to power up without blowing the fuse. To do that, remove the tubes including the rectifier, and disconnect the lead going to the selenium rectifier. Also make sure that the cap from the fuse holder to ground is not shorted, and that the pilot lamp holder isn't shorting the filament lead to ground. If you can't, then perhaps the problem is the power transformer.

You'll want to replace the selenium rectifier with a 1N4007, and replace the rest of the electrolytics.

The 1k5 on the 6V6 sockets are just grid stoppers, using pin 6 as a tie point.

[xtian]

What Martin said. You have to replace those paper-wrapped electrolytics!

Also remove the death cap!

[baritone61]

Hi, thanks for the tips.

I pulled the tubes, disconnected the lead to the selenium rectifier. Also disconnected the lead to the B+.
Death cap isn't shorted but I pulled it anyway.

Powering it up the transformer started buzzing and smoked a bit. I guess that answers that question...

Is the 8160 the correct power transformer for this amp? Everything I see online mentions the 5G9 with an 8160 as having a 108 output transformer and 14684 choke.

I was hoping to get away with not changing the other electrolytics to start with, but I'm sure it needs it.

[xtian]

Powering it up the transformer started buzzing and smoked a bit.

Rats! I thought you had a bulb-limiter in series?

Did you disconnect all the PT secondaries? I mean, it could be a short in the heater string or the bias circuit.

[baritone61]

Powering it up the transformer started buzzing and smoked a bit.

Rats! I thought you had a bulb-limiter in series?

Did you disconnect all the PT secondaries? I mean, it could be a short in the heater string or the bias circuit.

Hey. Yes, I disconnected all the secondaries.
I went back to the variac instead of the bulb tester.

The weird thing is I didn't find any shorts to ground. The primary leads had a resistance of around 3ohms.

[Stevem]

To test any PT for shorts get a 1 to 5 ohm ,5 to 10 watt resistor and wire it in series after the amps fuse on the way out to the ac cord.
Pull all the tubes out and fire up the amp with your meter set for ac and hooked up across that resistor,a good PT will read no more than .2 to .4 volts for that size amp as you bring it up slow on the variac ,any higher and your PT is toast!
Since your filters where so far gone this is the likely issue now that remains with the amp.