Epi Valve Jr Rebuild Help

[SeattleGreenhorn]

Are you using a pencil soldering iron for electronics, or a big gun made for soldering pipes?

I'm using the screwdriver tip that came with my Weller iron.

[ampgeek]

What is the wattage on your Weller?
Cheers,
Dave O.

[Gaz]

...most everything was coming up dead.

How do you know this from what you did? Capacitors, for example, should not read continuity unless they've shorted. A continuity test cannot tell you everything about components. Either way, if you're worried about ruining parts, you just need to adjust your soldering technique and/or soldering temp.

[SeattleGreenhorn]

You guys must be rolling your eyes so bad right now, haha. Thanks for sticking with this.

My buddy told me that same thing about a MM not being able to read clearly through components. Those Fluke MMs have a range setting on them, though, which allowed to get a clear continuity reading for every single cap and resistor. So, long story short, I didn't nuke anything, I just didn't know how to use a MM correctly.

I have a sneaking suspicion that my PT might be the problem afterall. That's the only stock part left on the amp, so it's the only "unknown" at this point. Since I can't see anywhere on the amp that I blew it and everything is checking out continuity wise I'm thinking I should just take it to a tech and see if he can find out what's going on.

[Gaz]

Haha, it's okay, I'm sure everybody reading this is reminded of what it was like when they first started screwing around with amps.

I agree that it's a mis-wiring thing, however whatever was smelling upon start up may have been ruined - that's not a bad assumption. One check you can do with the multimeter on the continuity test is hold one end to the chassis ground, and touch the other to all the point where there should be high voltage on your B+ line. There should no continuity, otherwise you would have a major short. You can also confirm your ground points this way as well, touch all of them with one probe while the other is on the chassis.

[fullwood]

have you joined sewatt.com yet? they have the voxy schematics that the watts boards are based on. The first amp I worked on was an EVJ V3 with the voxy mods (mostly), the bitmo trio, and the nfb-c3 out-c3 in switch. Since then i design and build all my own amps, but i still have that very first EVJ. The guys at sewatt know these amps like nobody else and they are a friendly bunch.
If you are interested there are a couple of videos of my EVJ still up on youtube, just look for my username there, "fullwood13".
Keep us posted on your progress and I will help where I can.

[renshen1957]

Ok. Here are my two schematics. They are crude and it would probably be a good idea to proof-read them with your layout, if you have either of these builds. Voltages are as they were taken from mine. The tube symbols were a quick draw, to get them on paper. I have since refine my tubes to more to my liking.

Hopefully, they will do someone some good.

Jack

Google put up this warning when I went to check out the "Marshall" schematic:

"Reported Attack Page!
This web page at ampgarage.com has been reported as an attack page and has been blocked based on your security preferences.

Attack pages try to install programs that steal private information, use your computer to attack others, or damage your system.Some attack pages intentionally distribute harmful software, but many are compromised without the knowledge or permission of their owners."

Paranoia or what.

Best regards,

Steve

[Colossal]

Just got my first malware warning when I posted a .png attachment in another thread. Using Safari.

[Jack Hester]

Google put up this warning when I went to check out the "Marshall" schematic:

Paranoia or what.

Steve -

Not paranoia. Just being safe, is a better term.

My files are automatically scanned by my PC-Tools anti-virus software. I've run into this before, but never the same circumstances. I have sent my drawings to my work email, to show sometimes, and our firewall may do the same thing at times. And, it's not consistent.

If it will let you download the file and open it on your computer, that may be the solution.

Jack

[Reeltarded]

I ran a scan and got this message:

The Dumble guys have cooties.

[Structo]

Yeah, there is a thread about this in the Garage.

After several warnings yesterday I did a scan with Malwarebytes and nothing came up.

I use that and Avast and neither gave a warning.

Only the browser did.

[renshen1957]

Yeah, there is a thread about this in the Garage.

After several warnings yesterday I did a scan with Malwarebytes and nothing came up.

I use that and Avast and neither gave a warning.

Only the browser did.

Hi Tom,

Any chance that someone from The Amp Garage will contact Google to lift their "Papal Bull" against TAG.

Stupid stuff like this get's one website listed with malware sites (Freeware downloads pages, Search Engine Hijackers, etc.) in some Anti-Virus and Malware software. I would hate to think potential new members scared away by being blocked by Norton or Viper (fill in the blank) as being banned or forbidden pages.

Best regards,

Steve

[guitardude57]

Ok. Here are my two schematics. They are crude and it would probably be a good idea to proof-read them with your layout, if you have either of these builds. Voltages are as they were taken from mine. The tube symbols were a quick draw, to get them on paper. I have since refine my tubes to more to my liking.

Hopefully, they will do someone some good.

Jack

Wow, never had that happen on here before.

[SeattleGreenhorn]

Hey guys, here's an update on my progress: I work at a non profit research institute (don't worry, I'm not a scientist, I do the shipping & receiving) and I found out that we have a guy here that is a wiz electrical engineer. We hooked the PT up to his super nice MM in his workshop and he says that my PT has a short in it. It's on the primary side so, praise the lord, it's not my fault that it blew! Haha, at least that's what the engineer said. So, now I'm in the market for a new PT. As far as I know my choices are a Heyboer through Watts Tube Audio for $95 plus shipping, or I can have my buddy at work order me a Hammond 269-AX for $50.

Here's a question for you experts out there: The Hammond has a 6.3V and a 250V secondary while the stock PT has a 6.3V and a 260V secondary. Will the 10 less volts coming off the Hammond make a big difference or mess with the amp at all?

[guitardude57]

10 volts unrectified is not that much off.
Use either one.