Tube console help

[barberbasses]

You're doing a great job. Those wafer tube sockets can be pretty flaky by this stage, so replacement is good. No harm in using small bolts instead of rivets.

My only comment for your next restoration (!) is to do the electrical rebuild in stages. First just replace the can filter caps and the coupling caps to the grids of the 6BQ5 tubes and get it working. Once that's done, replace other components as needed and check that it's still working after each change.

Thanks Dandy, clearly this can get a little out of hand unless you go in stages. In this case, i figure if I'm in there I may as well get some of these things cleaned up. I should have more time this weekend to get work done.

thanks

 

[Dandy]

Hope it all works well. (It's just been my experience that I have sometimes messed things up when cleaning them up.)

 

[barberbasses]

I inserted the new tube socket, works well. Eventually I'll probably do them all.

Good news, I was able to get signal out of one of the channels. Bad news, I'm only getting heater on the new tube socket tube so I've got something wrong. In the photo you can see, I've got a wire on the top tube socket incorrect, kudos to anyone who sees it( it's a EL84 tube). After I had it together and I was checking my work, I found an issue an corrected it. While I was getting signal from my source, it wasn't right.

Now I'm not getting any signal, I'm only getting heater on the tube with the new tube socket. I have a couple more connections to check, I had to stop working on it due to other commitments. I'm going to have time tomorrow to work on correcting the wiring. Although I had good notes and photos, I know I made a couple mistakes.

 

[barberbasses]

After getting all the tubes to light up I'm getting a pretty load sustained/honk and hum that I can see is directly related to the tube heaters. Even after powering down the unit the honk remains until I see the heater elements cool/dim.

checking for bad connections and shorts....

 

[gadget73]

that sounds more like open grounds than anything heater related. Heater and power supply hum stops as soon as the power is turned off, but signal passes until the heaters cool and the caps discharge. Open ground or ground loop will not change power on vs power off.

 

[barberbasses]

Hello everyone, sorry for the delay, life gets in the way.

After reading and researching data on this amp, schematics, etc....i found I was over my head. This unit was simply too challenging for my abilities.

I found a local gentleman that repairs vintage equipment, gave him a call, and he accepted my "project". After spending a couple weeks with the unit he noted there were a number of things missing or plain wrong. For example, he had to add another 12 volt tab because the new transformer, installed by the previous owner, wasn't the correct type.

All in all, the experience was a humbling one at the least. In this case I picked an amp that was way over my abilities. The challenge was it came to me extremely cheap and out of nowhere so I felt I had to try!

All that said. The amp is up and running, the only thing I've not done is put in the magic eye tube for the tuner which I don't use, maybe down the road.

I've got the unit set up with my Garrard TT, it sounds great and has plenty of power to run my Monitor Audio RS 6's.

Next up, the horns and speakers came out of the console, i'll probably make those into a new set of DIY speakers