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

Thread Closed
Thread Rating:
  • 2 Vote(s) - 2.5 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Philco 40-140 Field Coil Replacement
#39

Radiola, again, assuming no objectionable hum all is well. It might be interesting to see what the B+ is after the dropping resistor just to see how closely your resistor matched in reducing the B+ to the original field coil if you have any voltage levels indicated in the schematic. You should be set to go. Most all of the later tube radios like the AA5s never used a choke and had permanent magnet speakers, so no field coil. Generally they had higher value electrolytic caps to make up for the loss in filtering and most important, keep the cost of manufacturing down.
Bear in mind, I'm not the sharpest on radio repair but have a couple radios running speaker replacements using the resistor method and all have worked nicely for years.

Jerry

A friend in need is a pest!  Bill Slee ca 1970.


Messages In This Thread
Philco 40-140 Field Coil Replacement - by radiola - 09-05-2012, 12:21 AM
RE: Philco 40-140 Field Coil Replacement - by jerryhawthorne - 10-12-2012, 01:38 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
1949 Motorola 5A9M
Hello All; I found the CMB41L down in the basement, it is definitely a 1950-51 model, the capacitors have date codes ...Arran — 07:48 PM
Philco 42-345 Restoration/Repair
Hi, all the caps I order, other than the electrolytics, are of the 630V rating. No worries on it being too high, and no ...gary rabbitt — 05:46 PM
Philco 42-345 Restoration/Repair
Hi, there's a lot to consider when designing these circuits so you shouldn't have a lot of concern when replacing caps. ...RodB — 02:03 PM
Philco 42-345 Restoration/Repair
I have ordered and received new caps for this radio and hope I've ordered the correct ones. I tried matching them to the...osanders0311 — 11:35 AM
Philco newbie with P-1891-WA console questions
Hello Jeff , Far as the Electrolytic capacitors go here is a list of parts. that will work . I like using Nichicon and...radiorich — 09:50 PM
Philco newbie with P-1891-WA console questions
Well, I've been stumped at trying to get the first of 11 electrolytic capacitors. I got a schematic and have a list of t...Jeffcon — 07:54 PM
Model 80 Antenna Issue?
Thanks Gary and Rod.  I also found an article in the Philco Repair Bench under Service Hints and Tips, about installi...Hamilton — 12:32 PM
Model 80 Antenna Issue?
Hello Hamilton, here is a little information found in our Philco Radio Library at the bottom of the Home page. Hope it ...GarySP — 11:28 AM
Model 80 Antenna Issue?
I did as you suggested and touching the middle of the volume control did nothing so the coil has to be rewound. Any idea...Hamilton — 10:19 AM
1949 Motorola 5A9M
This would be the second portable in the "other radios" forum where I have a similar one in my collection. I h...Arran — 12:41 AM

[-]
Who's Online
There are currently 1314 online users. [Complete List]
» 2 Member(s) | 1312 Guest(s)
AvatarAvatar

>