Recent content by dgaggi

I'd have to do the math but I'd say very little or they'd have a bigger diode. Just finished a '66 ProReverb a few weeks ago that had a bad one. Not looking to go back into this amp for an 80 cent part that has nothing to do with tone is all.

Ok. Understood. When you say it has nothing to do with the voltage, that's not entirely true. It's a critical part in changing that AC into the required DC. I don't want to trust a possibly 56 year old p-n junction to do the rectification in that circuit. It very well may work for another 50...

Yes. Avionics. Component level repair.

Nothing? So it's not a rectifier? I know how a diode works thanks.

Great information Beans and thank you! Keeping your post for reference. Interesting about the external speaker jack. I wouldn't have thought to look at that. I've looked and the isolation washers are there. I've also read that there can be significant drift in the PEC modules. I will inspect...

It's the key component for the negative bias voltage.

Totally agree geezer. I've fixed modern amps that cost hundreds on their way to the scrap heap because of an inexpensive part. I much prefer vintage tube amps though. They each seem to have their own soul to me and I enjoy preserving the history. Good luck getting schematics for anything modern...

Yeah, I like that about the bias circuit also. ..and it's better than messing around and hooking up a decade resistor to find that sweet spot and then repeating that process the next time you change output tubes. A little dab of locktite or white out on the head after adjustment and done. The...

Never quoted specs. Just reading what it should be as per the schematics and the tolerances. The plan for now is getting it back to being solid and going from there. I'm not going to change the tone boards out unless something is bad. Figured while I was ordering the bias boards that I would...

Yup! Only changing out the electrolytic caps. The Mallory can has been in for 56 years. My math was off. The amp is two years older than me. lol The Ducati cap 25uf 30vdc is getting replaced. I've been on the wiki and I'm adding the bias adjust circuit just to make adjusting the bias easier for...

I'm going to check the voltage off of the diode once it's recapped. I wanted to know what to use to replace it if the voltage was off. I'm going through this amp with a fine tooth comb. The last tech that was in here was less than stellar. This is what it looked like when I opened it up. Yes...

Thank for the replies. Will check the resistor beans. Thanks for the heads up. New cap is in.

Ah ha! Never mind. Found the data on this rascal and no, a 1N4007 would not work.

I have my B-15 on the bench giving it some much needed love. My question is about the bias diode. The schematics have a part number of 10 D 6 for the diode. I cannot find any data on this creature. I don't want to assume that a 1N4007 is a suitable replacement until I know more about the diode...

I own a 1965 B-15NF that I'm currently restoring. Recap...etc. I'm an electronics tech and restore vintage amps. I know that I'm going to get poo-pooed but my daily drive is a Bugera Veyron Tube into a Peavey Headliner 4X10 Cab. Nothing sounds like the B-15 but this rig gets close enough for me...