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Hoffman Amps Forum image Author Topic: Off the subject  (Read 4001 times)

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Offline firemedic

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Off the subject
« on: May 11, 2011, 12:38:12 pm »
I have a guy wanting to sell me an old Victor 3VF305 tube stereo/tuner/phono that's not working right. I'm having a hard time finding a schematic for this thing & the online sources I have found are either virus-laden or very hush-hush about the info they have. I would jump right in but the rules must be different for amps of this kind, than what I'm used to. Any suggestions?
BTW it is a 6-speaker, EL84 power section. That's all I got. 

Offline RicharD

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Re: Off the subject
« Reply #1 on: May 11, 2011, 01:08:36 pm »
I have a schematic for a Victor MST-30.  This is a stereo 6BQ5 (2 per side) amp.  I hot rodded it into a stereo Stout.  That thang was full of premo parts, classic tubes, wire wound dog bone resistors, etc.  One of the best sounding geetar amps I've built.

Offline VMS

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Re: Off the subject
« Reply #2 on: May 11, 2011, 01:22:10 pm »
Schematic can be found here (RCA):

http://techpreservation.dyndns.org/schematics/


Offline firemedic

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Re: Off the subject
« Reply #3 on: May 11, 2011, 07:56:11 pm »
When I tried that site, my computer threw up a bunch of red flags warning that the site is unsafe. You sure it's safe?

Offline PRR

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Re: Off the subject
« Reply #4 on: May 11, 2011, 09:12:03 pm »
> http://techpreservation.dyndns.org/schematics/ When I tried that site, my computer threw up a bunch of red flags warning that the site is unsafe. You sure it's safe?

What exactly was "throwing flags"? The browser? A browser plug-in? A virus-checker? A firewall?

Put "techpreservation" in Google and see if anybody has posted complaints:
http://www.google.com/search?q=techpreservation
Many links reference it, and many say "it's down!"; one about a file-view glitch. I do not see any reports of infection.

McAfee's Site Advisor has a page:
http://www.siteadvisor.com/sites/techpreservation.dyndns.org
"didn't find any significant problems."
"downloads on this site were free of adware, spyware, and other potentially unwanted programs."

techpreservation.dyndns.org is, on the face of it, a "dynamic DNS" site. This means its numeric address changes, is not semi-permanent like "real" websites. It is probably hosted on a non-commercial connection, the IP address changes each time the PC reboots or the ISP refreshes their connections. While this is "unusual", it should not throw flags.

Offline firemedic

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Re: Off the subject
« Reply #5 on: May 11, 2011, 09:29:14 pm »
Okay, that helps clear it up. It's my computer's default firewall making noise, Norton is conspicuously silent about it. Thanks PRR...

Offline PRR

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Re: Off the subject
« Reply #6 on: May 11, 2011, 11:18:20 pm »
Experimenting with DVU to PDF conversion....

Offline DummyLoad

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Re: Off the subject
« Reply #7 on: May 11, 2011, 11:39:48 pm »
Experimenting with DVU to PDF conversion....


http://www.docspal.com/  

online converter...  :)

schematic attached in .pdf format.

edit: ooops!!!  i saw your schematic attachment *after* i posted... sorry.
« Last Edit: May 11, 2011, 11:43:20 pm by DummyLoad »

Offline firemedic

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Re: Off the subject
« Reply #8 on: May 12, 2011, 07:56:51 am »
Wow, thanks guys. While youse guys were busy helping me I downloaded all the stuff for the djvu file, took almost an hour.
That looks like a very cool power amp. If the cabinet was all torn up I would convert it to a guitar project  without a second thought. But it's in fairly good shape so I expect I'll try to rehab it to original specs. Man that's a lot of tubes I don't have.....

Offline jjasilli

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Re: Off the subject
« Reply #9 on: May 12, 2011, 09:23:41 am »
Riffing off Buttery's reply, what would you do with this amp:  Restore it; or strip it to build a guitar amp? 

If the former, some guys choose to forego the antiquated tuner and phonograph, and use just the power amp section, maybe the preamp too.  That will simplify things if you need to trace out your own schematic for just or those sections.

If the latter, then just strip away!

Offline firemedic

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Re: Off the subject
« Reply #10 on: May 12, 2011, 10:09:07 am »
I haven't seen it except on craigslist pictures. With just one (family) owner the cabinet looks pretty mint. I'll have to assess the condition of the tuner & phono before making the decision. Got lots of vinyl.  I believe its dual single-ended el84 output sections which is freakin awesome. The possibilities.....

 


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