Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

Philco 90 filament section on PT bad
#5

Well I am stumped.  I have removed the transformer completely.  I took the shields off, checked all the connections, one of the filament leads looked a little loose, so I resoldered it.  I put the transformer back together, checked all the ohms and unloaded voltages. I then took two 27 tubes, and four 24 tubes and wired the filaments up per the schematic with jumpers on my bench.  I wired them to the transformer and powered it up.  The filament voltage unloaded is 2.7v and with the 24&27 tubes hooked up ONLY, the voltage drops to 1.5v.  The current draw is 8amps.   Below is the voltages on the leads with and without the filaments of the 24 and 27 tubes hooked up.  

With 24&27 tubes hooked up only
Pri: 115vac.    .3 amp draw
Sec HV: 732vac
45 tube filament: 2.7vac
80 tube filament: 5.4vac
24&27 tube filament: 1.4vac

Without 24&27 tubes hooked up
Pri: 115vac   4.0ohms

Sec HV: 737vac.  237ohms
45 tube filament: 2.7vac.   .2 ohms
80 tube filament: 5.5vac.   .4 ohms
24&27 tube filament: 2.7vac.   .2ohms


Messages In This Thread
Philco 90 filament section on PT bad - by Skip - 04-02-2016, 02:08 PM
RE: Philco 90 filament section on PT bad - by Skip - 04-02-2016, 07:34 PM
RE: Philco 90 filament section on PT bad - by OZ4 - 04-03-2016, 12:02 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
hello david, I have a similar generator in my collection that features a cast iron, single-cylinder Briggs & Stratt...radiorich — 01:00 AM
under chassis parts locator diagram for 1938 Zenith 9s262
Has anyone gone to the trouble of creating an under chassis parts locator image?  Yes, I can identify components by foll...bobloney — 08:57 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Try looking at this site the book mark is for a old generator that I was given. David    https://radionerds.com/index.ph...David — 08:36 PM
Plug Voltages Needed For A 1943 CRV-20130 Power Supply
Hello Everyone, I am looking for voltage identification for all the pin positions on the socket of a CRV-20130 power su...Tonym4704 — 08:16 PM
Philco P45-6365 Universal Transformer Instruction Manual
Can anyone guide me to where this may be found?GRG — 03:00 PM
54C Complete Teardown/Rebuild
I don't think that I have encountered a 12Z3 before, curious how it uses one of those but includes a #43, which is a 25 ...Arran — 02:17 PM
HiFi (Chifi) tube amp build - but my own design.
It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM
Philco 71 Code 125
Hello,  I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM
Stromberg Carlson 1500 Squeal
And life just keeps getting more complicated.dconant — 07:57 AM
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM

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

>