Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Tubby i mean tube ?
#4

Fred;
  I looked up the 6F7M and the 6P7G, the tubes are identical electrically other then the pinout, same voltage and current ratings, same amplification factors, same transconductance. I think that like many tubes decided to make a spray shield version of a standard RMA tube type such as the 6F7 by coming out with the 6F7S. When octal based tubes hit the market in 1935-36 they decided to manufacture an octal version of the 6F7S and called it a 6F7M whereas when either RCA or Sylvania decided to make an octal version of a 6F7 they called it a 6P7 or a 6P7G but used a different pinout. The reason I looked into this is that I just acquired a Rogers set that happens to use a 6F7M, but unlike your Deforest-Crosley someone has replaced most of the spray shield tubes with metal ones, and I have not investigated if they replaced the 6F7M tubes with something else or how they did so.
Regards
Arran

P.S What model is your Deforest-Crosley? There should be a name stamped or stenciled somewhere in the back of the cabinet. Also what's the chassis model number? It should be something like 7DXXX.


Messages In This Thread
Tubby i mean tube ? - by Fred Taylor - 06-08-2015, 07:34 PM
RE: Tubby i mean tube ? - by Arran - 06-09-2015, 12:31 AM
RE: Tubby i mean tube ? - by Fred Taylor - 06-09-2015, 09:58 PM
RE: Tubby i mean tube ? - by Arran - 06-09-2015, 11:58 PM
RE: Tubby i mean tube ? - by Fred Taylor - 06-10-2015, 06:50 AM
RE: Tubby i mean tube ? - by Arran - 06-11-2015, 01:07 AM
RE: Tubby i mean tube ? - by palegreenthumb - 06-11-2015, 01:11 AM
RE: Tubby i mean tube ? - by Dan Walker - 07-15-2015, 12:07 AM
RE: Tubby i mean tube ? - by Arran - 07-15-2015, 12:57 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Jackson 715 not working
Now that you posted the schematic, I don't know why that Sprague electrolytic cap is across the meter, as it is not indi...MrFixr55 — 05:51 PM
HiFi (Chifi) tube amp build - but my own design.
What may be lacking in the PP Tube amps may be the 2nd harmonics, which some, especially RCA back in the day called &quo...MrFixr55 — 05:32 PM
Jackson 715 not working
Usually in an emission tester, the tube under test is measured as if it were a diode. So, some testers connect all the g...RodB — 04:17 PM
Restoring Philco 37-604C
Yep. F5 is green, D5 is Red. Red is Bad. Green is Clean.morzh — 01:30 PM
Jackson 715 not working
I did start to do that but I stalled out because I could not figure out how the grid and plate get voltage. In this diag...daveone23 — 11:52 AM
Restoring Philco 37-604C
(Insert Homer Simpson "DOPF" Here.) When all fails, look at the can. Took the Ron Ramirez advice, red Caig D...MrFixr55 — 09:23 AM
Philco 91 Speaker Replacement
From your text I am not sure if you intend to use the existing speaker with a resistor instead of the field coil. It wo...morzh — 08:44 AM
Philco 91 Speaker Replacement
My field coil is bad. I am still hoping to find an original, but if I can't I will go with a fitting Philco speaker, 125...dconant — 08:34 AM
Philco 91 Speaker Replacement
As Rod said, it is OK to use a fitting speaker, and then look for an original one. If you buy a Hammond 125 output tr...morzh — 08:15 AM
Philco 91 Speaker Replacement
Yes, I often have to substitute, then keep an eye out for an original. In the meantime, the radio is working and being e...RodB — 08:02 AM

[-]
Who's Online
There are currently 5246 online users. [Complete List]
» 1 Member(s) | 5245 Guest(s)
Avatar

>