Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

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

Philco 90 with Twin 47 Tubes in PP
#5

joybird Wrote:Does not JIVE.

Definitely not! The 90 with 2-47 outputs uses the same type of autodyne oscillator circuit as the 71, 91, 19, 89 and a few others. Yup, the very same circuit that has made many a young man's hair turn gray.

That circuit must have the 700 pF cap (13) and a 10K (or better yet, an 8.2K) resistor in place of the factory-designated 15K (14). The det-osc tube (24) will not oscillate without the 700 pF cap, and it most assuredly will not work with a 56K in place of the 15K.

3615-AJ - part (9) on schematic - should definitely be dual .05 uF, not dual .09. I see the schematic on my site erroneously states .09 uF, as does the Rider data (which is the factory data from Philco).

Another "OOPS" moment brought to you by Philco. Icon_rolleyes

--
Ron Ramirez
Ferdinand IN


Messages In This Thread
Philco 90 with Twin 47 Tubes in PP - by joybird - 05-05-2014, 12:00 PM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-05-2014, 03:39 PM
RE: Philco 90 with Twin 47 Tubes in PP - by Ron Ramirez - 05-05-2014, 04:46 PM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-05-2014, 04:55 PM
RE: Philco 90 with Twin 47 Tubes in PP - by Arran - 05-05-2014, 06:23 PM
RE: Philco 90 with Twin 47 Tubes in PP - by Arran - 05-05-2014, 07:05 PM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-05-2014, 07:45 PM
RE: Philco 90 with Twin 47 Tubes in PP - by gregb - 05-05-2014, 09:45 PM
RE: Philco 90 with Twin 47 Tubes in PP - by gregb - 05-05-2014, 09:49 PM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-05-2014, 10:37 PM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-07-2014, 02:21 PM
RE: Philco 90 with Twin 47 Tubes in PP - by Arran - 05-07-2014, 11:48 PM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-14-2014, 11:15 AM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-14-2014, 02:11 PM
RE: Philco 90 with Twin 47 Tubes in PP - by gregb - 05-14-2014, 04:22 PM
RE: Philco 90 with Twin 47 Tubes in PP - by morzh - 05-15-2014, 01:26 PM
RE: Philco 90 with Twin 47 Tubes in PP - by Arran - 05-16-2014, 01:09 AM
RE: Philco 90 with Twin 47 Tubes in PP - by Arran - 05-17-2014, 02:40 AM



Users browsing this thread:
[-]
Recent Posts
Need to purchase some accessories for restoration of my Old Philco Radio
Hi Paulo, Welcome to the Philco Phorum. I can see why you want to find good reproduction parts. That is a bea...MrFixr55 — 11:10 PM
HiFi (Chifi) tube amp build - but my own design.
Tim, I have some bakelite sockets in my work shop that I can dig up. I believe quite a few are NOS. I will take photo...RodB — 10:03 PM
Philco 610B oscillator wiring
> The cathode as noted is wired directly to the ground side of the heater filament for that tube, not to the #17 and ...Radioroslyn — 08:12 PM
HiFi (Chifi) tube amp build - but my own design.
Tim; I noticed your post a little late, but I would take one of the junk sockets and try to break a chunk out of it wi...Arran — 08:07 PM
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM

[-]
Who's Online
There are currently no members online.

>