Philco 41-255 - Printable Version

Philco 41-255 - Printable Version

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Philco 41-255 - RichG - 07-01-2025

Greetings! Just thought I'd share my latest restoration project. The cabinet looks to be in decent condition as does the chassis. Someone, at some point, attempted to fix the radio. The capacitor input to the filter is way too high for the rectifier tube, it should be more like 12mfd not 30mfd. The push button power switch is toast, so it was bypassed with a volume control/power switch. I may try to repair the push button switch but it is part of the bush button assembly and I may not be able to get it apart (or more importantly, get it back together!). Tube checking is next on my list. Replacement caps are currently on order. The wiring looks to be in good shape.
If anyone has any advice on what to look out for, please let me know. I've posted some pictures.
Thanks everyone!
Rich

RE: Philco 41-255 - RichG - 07-01-2025

Oh, I forgot to mention. I will be re-wiring the 120V power cord, possibly with something more period correct. It's probably just me, but I don't care for switching the neutral, would rather switch the hot leg. That and the safety caps (residing in the bakelite box) will be replaced and placed after the power switch.
Rich

RE: Philco 41-255 - MrFixr55 - 07-01-2025

Hi Rich,

I actually have this radio! A nice performer, although with only 180V, a little light in the audio output department (2W). Yours looks very nice, likely from a non-smoker. How rare! Certainly, change all of the electrolytic and paper- foil caps in this set and verify all resistors in the audio output stage. This set uses a very unique method for getting the 180 degree out of phase signal for the 2nd output tube in the push pull circuit: They do not use a phase inverter stage; they get it from the screen of the first tube through a resistor. Verify that resistors 53, 54 and 56 are as close to dead on as possible, same with the resistor #61 which biases the output stage. If distortion is too high, switch the 2 41 output tubes with each other or try to get a matched pair.
I upped my filter caps to 30 uF and 30 uF but it is because I had a bad field coil and replaced the speaker with a modern PM speaker and a 1100 Ohm resistor. The RCA Receiving Tube Manual states that for input cap values greater than 40 uF, a higher impedance input to the tube is needed, so I think I am OK with the 30 uF caps. However, there are those who state that this is a rather weak tube.

I agree 100% about not switching neutrals. This is not an AA5 set where they switched the chassis side of the set. The nice thing about this set is that being transformer powered and that the EMI caps from both "legs" of the power line tie to the chassis, neither side is really neutral. The downside is that either way, there is a little "tickle because both EMI caps tie to the chassis, leaving it at about 60V above ground regardless of which way the plug is inserted into the outlet. To ensure that the switch is in the hot side and that the EMI cap on the hot side is switched, put one EMI cap after the switch and that ensure that the power lead going to the switch is on the skinnier prong of a polarized plug.

My set came with a replaced power cord, but I am almost positive that the power cord for this set was rubber, had strain relief molded onto it, a molded rubber non-polarized plug (they did not make polarized plugs until the 60s or 70s), and a yellow UL label wrapped on one end. I do not believe that the cable was cloth covered.

I can't read the station tags on my set; I bought it from eBay about 10 years ago. Based on the station tags on your set, (WJZ, WEAF, WHN, WNEW, WABC) your set came from the New York Metro Area, my neck of the woods.

There was someone who makes the Tenite escutcheon plates for this set, but I can't remember who. You can google Escutcheon plate for Philco 41-255 and see what happens. They always shrink and crack. Same with the buttons.

For the switch, you can drill out the rivets. A similar power switch with a rotating button is still made, so you may be able to swap the contacts from the new switch into the original one

Hope this helps.

RE: Philco 41-255 - RichG - 07-02-2025

Hi MrFixr55
The radio seems to have been well cared for, no musty smell, no nests etc. I have replacement resistors on order. It's been my experience that many of them drift quite a bit. I decided to replace all of them. Though I think the 1.8 ohm resistor in series with the station lights could probably drift a bit and not be a problem. I thought the same as you based on the station call letters that it originally came from NY. I thought the escutcheon plate was tenite but wasn't positive. It is warped a fair bit. I will look around the web to see if one can be made. Who knows, I flattened the tenite disk on my 39-116 remote control by putting it in hot water and clamping it between two metal plates. I will be checking renovated Radios to see if they have escutcheons. I did see a couple of posts here about replacing those push button on/off switches. I found a Hillman switch that may be a possible replacement. The existing switch is quite small and there's not a lot of room for anything much bigger.
Thanks for the info!
Rich

RE: Philco 41-255 - RichG - 07-05-2025

I did find an escutcheon from Renovated Radios. He also has the buttons. The buttons on mine seem to be okay but the escutcheon is warped pretty badly even though it has a small U shaped brace across the width of the plate. I will try to replace the push button on/off switch. I found one at Lowes that might work, just need to check the size. All the tubes test good on my Jackson tester. Even the 41 output tubes register very close to one another on the plate transconductance. Parts should be here next week. I will be checking the wiring but so far, it appears that there is little to no rubber insulated wires. The rubber insulated wires that are there are still soft and flexible.
Rich

RE: Philco 41-255 - MrFixr55 - 07-05-2025

Hi Rich,
I figured that I would give you a little history regarding the station tags on your radio. (Edit- This turned out to be a little bit more than a "little history", and I may end up transferring this to a new Thread. This will explain the frequencies that they are tuned to: (Edited again 7/18/25 to correct mistakes)

New York City was home to the flagship stations of several networks and several radio manufacturers, including Greebe, Emerson, FAD Andrea (FADA), Federal, Freed Eastman, etc. Lee DeForest had labs and manufactured Audions in Bronx. RCA's headquarters was originally in the Wanamaker Building in lower Manhattan. AT&T's Bell Laboratories and Western Electric were also in NYC. Rockefeller Center, built in the 1930s, became home to RCA's National Broadcasting Company. The NBC Studios were known as "Radio City". This likely influenced the naming of the theater in Rockefeller as Radio City Music Hall. The stations that I can make out on your picture are WEAF, WOR, WJZ, WABC, WHN and WNEW

WEAF (Later WNBC, now WFAN, 660 KHz) was first founded by Western Electric and AT&T, became part of an AT&T "Chain" (Network), and was transferred to RCA in 1926. It was assigned a frequency of 660 KHz by the FCC when the broadcast band was established from about 550KHz to about 1500 KHz. This became WNBC, at 660 KHz, the flagship station of the NBC (National Broadcasting Company) "Red" network, and a "clear channel" 50 KW station. (There was also a Blue Network, centered around WJZ until regulations forced NBC to divest itself of the Blue Network. In the early 1980s, WNBC changed its format from music to Talk and featured both Don Imus and Howard Stern. In 1989, after the GE takeover of RCA, GE divested the National Broadcasting Company of all AM radio stations. Eventually, WNBCwas sold to Emmis Broadcasting where it became WFAN, which was previously operating at 1050 KHz.

WOR (710 KHz) holds the distinction of having the longest record for using the same call letters and the longest use of the same frequency. In addition, they are one of the very few stations that have only 3 letters in their call sign. Originally started by Bamberger's Department Stores, in 1927, it became the flagship New York City outlet for CBS (Columbia Broadcasting System) and was assigned 710 KHz as a clear channel, which it has occupied since. In 1934, after CBS took over the Atlantic Broadcasting Corporation station that eventually became WCBS, WOR allied with several other stations and became part of the Mutual Brodcasting Network, the 4th of the Big 4 Networks that also included NBC Red, NBC Blue which became ABC), and CBS. WOR left Mutual in 1957 and became an independent. WOR played Adult Standards and MOR (Middle of the Road) music, news and variety talk programs, eventually moving to all talk, including such famous personalities as Bernard Melzer, Arlene Francis, Dorothy Kilgallen and her husband Dick Kollmar, and Rush Limbaugh (who moved from WABC). From 1925 to 2000, WOR hosted a talk show "Rambling with Gambling" Hosted by John B. Gambling, then his son John A. Gambling and finally grandson John R. Gambling. IMHO, the Gamblings were unique as "gentlemen" of the talk show genre as opposed to the various angry pundits and shock jocks.

WJZ (Now WABC, 770 KHz) was founded by Westinghouse shortly after they established KDKA, arguably the first commercial broadcast station in Radio History. In 1926, this station and its affiliated network stations fell under the control of RCA where it eventually became the NBC "Blue" network, broadcasting at 760 KHz untill1941 when it was assigned the 770 KHz clear channel frequency. Regulations regarding ownership of more than one AM radio station in the same service area forced RCA and NBC to divest itself of the Blue Network in 1942. The Blue Network became the American Broadcasting Company (ABC) in 1945. WJZ became WABC in 1953 when the call sign WABC was made available when the station holding those call letters was renamed WCBS. WABC became the #1 Rock and Roll Top 40 AM Station in the New York area with DJs such as "Cousin Brucie" Morrow, "Dandy Dan" Ingram, Ron Lunday and others. When listeners moved to FM and WNBC, WABC went to the news / talk format that they hold to now.
The American Broadcasting Company was bought by Walt Disney, INC who divested ABC of all stations not carrying Disney or ESPN programming. Currently, WABC is owned by Red Apple Media, where it retains its News / Talk format.

WABC (Now WCBS, 880 KHz) started out as WAHG, founded by Alfred H Greebe, founder of the Greebe Radio company, in 1924. Greebe founded another radio station, WBOQ (Borough of Queens), and caused the Atlantic Broadcasting Company to be formed. These stations were eventually consolidated and later named WABC. WABC was eventually purchased by the Columbia Broadcasting System (CBS), was assigned a clear channel frequency of 880 KHz and renamed WCBS. CBS played "American Standards" and had news and variety programs until gradually changing its format to "all news" in 1967 and completing the changeover in 1970. WCBS ran an all news format until 2024 where it became the outlet for ESPN.

WHN (1050 KHZ) was founded in 1922 by the Ridgewood Times newspaper, was assigned the frequency 1050KHz in 1941. WHN eventually was owned by Loewes who owned the MGM (Metro-Goldwin Meyer) movie studios, changing the call sign to WMGM in 1948. The call sign was changed back to WHN in 1962. WHN had a broad spectrum of programming over the years, including popular American standards, drama, comedy, news, variety, quiz shows, sports, including hosting the Brooklyn Dodgers and later the New York Mets as well as other sports teams. The format eventually changed to Top 40, Country, Talk, and eventually ESPN, then Spanish Language, and now English again.

RE: Philco 41-255 - RichG - 07-06-2025

MrFixr55,
Now that is a history lesson for sure!! Awesome work on the station history. I only recognized WOR, WABC and WNEW as NY stations. I do remember listening to 'Cousin Brucie' as well as 'The Swingin' Soiree with Murray the K' on, I think, WINS. For some reason I thought WJZ was a Boston station but then realized I mixed it up with WBZ.
I am attempting to fix the on/off switch. I took it apart and realized one lead had partially pulled out and was making intermittent contact. I found it weird that the lead was not soldered to the spring leaf. But then realized soldering would probably ruin the spring action that the rotor depends on. I have new leads installed and the switch works properly. Now just need to figure out how to re-attach it. I may try to figure out a way to use #4 40 screws in place of the rivets. I may end up removing the push button switch assembly.
Thanks again for the station history. It was nice to know what happened to stations I had never heard of.
Rich

RE: Philco 41-255 - MrFixr55 - 07-07-2025

Hi Rich,

For some of these switches, the wires are merely pushed in and the edge of the contact digs into the wire. If the connector is made of plated spring steel and the area contacted by the wire is slightly "V" shaped, then that is how it works. Kinda like those cheap outlets where you just push the wire in the back.

Yes, I think that Murry the K was on WINS; he was a little before my time, but my late older sister or my older cousins would have remembered him. I did not mention WMCA, 570KHz, "The WMCA Good Guys". There were 2 other AM stations based on Long Island, WGSM (740KHz) and WHLI (1100KHz). here was a local Connecticut Station, WTIC, (600 KHz). I never heard the station, but a clock with their logo and frequency was in a local diner years ago.

I think that one of those buttons is for either "TV" or Phono. You may note a label that states "TV or Phono - The wireless way!" Philco was an early (Pre-WWII) producer of televisions, and many of their models or proposed models did not have a sound amp, figuring that the existing radios could fill the bill. I don't know what the frequency of the transmitter or the receiving frequency was. I assume that it was adjustable between 540 and 600 MHz. If so, then the button may have been used for a station at the beginning of the dial if the user did not have a wireless phono or Philco TV with this feature. RCA may have had a similar idea for TV, as some of their radios of this period had an "RCA Jack" labeled "Phono or TV" and a switch for that purpose. For years, both before and after WWII, RCA and many other radios had some sort of connection for an external phonograph, using the Radio's audio section. THese connections were also used for early FM convertors.

RE: Philco 41-255 - RichG - 07-13-2025

Just a quick update. I've been replacing capacitors and resistors in my radio. Some resistors are a different value than shown on the schematic (the ones shown in the production changes are correct). However, when I got to the output stage things got really confusing. I always check the schematic to make sure I'm working in the right spot. I found that the output tubes are not wired as shown in the schematic. Just by dumb luck I checked the model 41-256 and lo and behold, the output tubes in my radio are wired exactly like a model 256. I guess there were some production changes but these changes are major and not noted in the production change notes. I haven't checked every detail of the schematic, but it appears that only the output tubes are affected. Has anyone run across this kind of model change?
Thanks,
Rich

RE: Philco 41-255 - RichG - 07-18-2025

Hi All,
Just a quick update on my restoration journey. I did find that the output tubes are indeed wired like a model 256. My radio may have been a late model with some production changes that were not documented. Resistors 53 and 54 in the schematic now have a 470k resistor in series with the J line going back to B-. In the volume control/tone control circuit, I had trouble finding the 33k (41) resistor. Finally found it buried behind the volume control, except it was now a 100k resistor. The .01 uf cap (45) on the tone control had been changed to .003 uf. Lastly, the schematic shows 5 pilot lamps, one for each band (overseas, police, broadcast, push button), and one to light the dial. My radio only has two pilot lights. There is a nifty dial cord setup that pivots a single pilot light up and down as the band switch is changed. So far, I haven't found any info on how the dial cord pivot is setup. The resistor (67) for pilot lights was changed from 1.8 ohms to 2.7 ohms. All the other changes in component values were found in a couple of production changes. I ended up replacing all the resistors as the vast majority of them were way out of tolerance and those that weren't were at the upper limit of their tolerance. Since I haven't yet figured out how to re-use the push button on/off switch, I will, temporarily at least, use the on/off switch on the volume control.
A note for MrFixr55. There is a button for television, on the chassis it is labeled phone/television. There is a trimmer cap and oscillator coil for that button, but no indication of the frequency range like the other station buttons have. I haven't searched in depth for the instructions on how to set the television and radio to communicate with each other, but so far haven't found any.

Rich

RE: Philco 41-255 - MrFixr55 - 07-18-2025

Hi Rich,

My guess is that this audio wirelessly from TV was not used on production postwar Philco TVs. This is a Pre-WWII set and TV was just being introduced at this time. I haven't looked at mine in a while. Philco, as well as RCA and GE did make "phono oscillators that would broadcast the output of a turntable on the Standard Broadcast band. The oscillator would be tuned to a frequency not occupied by station receivable in the area.

RE: Philco 41-255 - RichG - 07-19-2025

Just another update. It's ALIVE!! Brought the radio slowly up on a variac. At about 100v, I began to hear static. At 115v, AM stations were loud and clear. I was able to receive a number of AM stations and the dial seems to be pretty accurate. Did not expect to get anything on the police and overseas bands and I didn't get anything except some static. Will try again in the evening. I will go through alignment procedures to tweak the IF and make sure the dial is set accurately. I haven't yet found clear alignment info for this radio. If anyone can point me in the right direction, I'd appreciate it.
Now I just need to order the tenite escutcheon and do some cabinet restoration. I'll look through the sections on cabinet restoration for some pointers on how bring the cabinet back and not lose the Philco decal. Though, I think the decal can be replaced. I'm not a purist when it comes to cabinet restoration, I just want it to look presentable. If there is lacquer finish, my only real option is a rattle can.
Thanks,
Rich

RE: Philco 41-255 - GarySP - 07-19-2025

Hello RichG! This should help with your alignment issues. In the schematic for your 41-255 is shown the compensator locations. It then says to follow the alignment instructions provided for the 41-280/41-285 schematic. You can find them both in the Philco Radio Library. Take care, - Gary

https://philcoradio.com/library/index.php/service-info/philco-1941-rms-year-book/

RE: Philco 41-255 - RichG - 07-19-2025

Hi Gary,
Great minds must think alike! I finally noticed a note in one of the schematics that the alignment procedure is the same as model 41-285. I found it in the 1941 RMS yearbook. Thanks for the information! This procedure looks straight forward and a bit simpler and more complete than the one I had been looking at. That one required a loctal adapter, which I'm guessing allowed access to the tube pins. This procedure just requires a loop of several turns of wire connected to the signal generator for RF padders and a .1 mfd capacitor connected to the internal loop antenna for IF padders.
On another note, I did try the push buttons. I was surprised to find that 4 of them actually were tuned to local stations even though they used to be NYC stations. The push button connections really do need a good cleaning.
Rich

RE: Philco 41-255 - RichG - 07-25-2025

Hi All,
Well, my alignment procedure for the IF sections went well. I did find additional info in the Rider books: Aligning Philco Receivers. The RF sections did not go as well. I'm finding most of the oscillator padders have no effect at all. The SW band is way out of calibration. WWV comes in just over 11MHz and the SW and antenna 12MHz padders have no effect. I'm going to check the band switch again to make sure I have all the contacts cleaned properly. There is also a chance that I miss wired the oscillator transformer. When I was changing the capacitors I noticed a wire from the oscillator transformer that wasn't connected to anything. By process of elimination I figured out the numbering of the transformer wires and connected the dangling wire to the proper terminal on the bandswitch. There's probably a good chance my elimination process did not go well. I guess there could be an issue with some of the windings on the oscillator transformer, though not likely. The AM band is working great though the dial is just a tiny bit off, KIXI on 880KC is 890 on the dial. While it's not likely that I will use the Police and Short Wave bands, I'd like to know that I got them to work and calibrated properly.
On another note, I did find that the volume control is not the original unit. This one has an on/off switch attached. Probably replaced when the push button on/off switch failed. While the total resistance is the same as the original, the tap is not quite in the same position. This doesn't seem to affect the volume control as far as I can tell. But I'm suspicious that it may affect the AVC line. Tuning to a close station like KIXI will swamp the AVC and cause a dramatic volume increase.
So, it seems I have a bit more work troubleshooting work ahead of me.

Rich