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Help w/ A National VAL-TREM Amp

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6/26/2000 9:11 PM

Help w/ A National VAL-TREM Amp

Hi:
I just acquired an old National VAL-TREM amp this weekend. It is a sweet sounding low power little 2 X 10 combo amp. It has 2 ea. C10R old Jensen Special Speakers. It is in very good condition and just needs some minor cleanup & tweaking ... I think!?

It has the following tubes:
3 ea. 6EU7 (Triodes !?)
1 ea. 5Y3 GT (Rectifier !?)
2 ea. 6973 (Power tubes !?)

I have found through references that I can sub 12ax7 family tubes for the 6EU7's, but I cannot find what the 6973's are comparable with ... (EL84's ???)

Please help me if anyone knows what to replace the power tubes with ... and anything else about this amp would be greatly appreciated.

Thank you in advance.

Lee

6/26/2000 9:14 PM
Leeq	P.S. I forgot to post this ... I'm sure it may be helpful for identification for y'all: It is National VAL-TREM MODEL NO. 1240 Lee

6/27/2000 3:34 PM
Leeq	P.P.S. I just found out that the 12ax7 family of tubes does not work with this amp. So now I need help with the whole device. Help you guys! It looks like I may have to modify it some if I'm going to use it at all and put new tubes in it ... Thank you in advance! Lee

6/27/2000 4:17 PM
Rebel420	12ax7 etc, use a different pinout than the 6eu7. A 6eu7 IS a 12ax7 with a different pinout, actually

6/27/2000 7:19 PM

Hi; I have a National Val-verb amp #1260. It also has 6973 and 6eu7 preamp tubes but has reverb instead of tremelo. It has 2 C10r's as well. I was disappointed with it's tone, and was unable to locate a schematic but found that a Gretsch was quite similar [I think it's called a dual or twin reverb] you can find it on gretschpages.com. After looking at the schematic, I thought the problem might be in the tone control circuit. It is quite complicated, and I thought it might be sucking the tone right out. I replaced it with a tone circuit out of a Tweed Deluxe, and boy did it wake it up!! It really smokes now. I personally don't think you need to replace the 6EU7's or the 6973's unless they are bad. I think it has wonderful tone the way it is now. Good Luck, Bill

6/27/2000 5:39 PM
Scott Swartz	You may be able to sub 6CZ5 for the power tubes. Pinout is similar to 6973, but 6973 has higher plate voltage rating (kind of like 6BQ5 vs 7189). I don't know what 6CZ5s are going for but has to be less than 6973s. Or just rewire the sockets to 6BQ5/EL84. All pinouts available at Duncan's Tube Search Database or whatever its called.

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