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

Thread Closed

my 41-81T starting with the battery....
#12

Very elegant solution to restore the innards of your battery. I didn't think you should solder to batteries without tabs (don't know why I thought that) so I made mine with 9 volt batteries in series for the B supply. I haven't had to replace mine in many years of light use, so yours ought to last forever with series AAAs.

Odd, but the Philco service package I obtained from Chuck Schwark seems to have contradictory specifications. First it specifies the P-41A-4G battery, which obviously produces a 61.5 volts nominal B supply. But the power specification on the same page specifies a 90 volt B supply.

I originally made my repro battery with 7 nine volt batteries in series to make 63 volts. The radio worked perfectly well. Later, when I'd bought the schematic from Chuck and saw the 90 volt specification I thought that maybe the 90 B supply in the spec would improve something, so I added 3 more 9 Volt batteries in series for 90 volts. Nothing in the radio's performance changed. I didn't make current measurements to see if that changed.

John Honeycutt


Messages In This Thread



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
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
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM
54C Complete Teardown/Rebuild
The main problem with adding a Bluetooth input is that this set lacks a traditional power transformer to isolate it from...radiorich — 11:19 PM
54C Cabinet Refinish
I started stripping this cabinet before it got super chilly out because I knew I wasn't going to be able to work on ...glyphmon — 11:18 PM

[-]
Who's Online
There are currently 1583 online users. [Complete List]
» 2 Member(s) | 1581 Guest(s)
AvatarAvatar

>