UPDATE: Tubes tested. Canadian Philco Radio: ID and repair needed
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Hey, all. This is my first post. I just picked up a tube radio at a flea market. This is my first Radio and I think I may have caught the bug. These things are way cool!
I cannot ID this radio, nor get a schematic. The chassis label is also missing.
It's a 5 tube Canadian Philco with an 1A7EG, 1N5EG, 1H5EG and 2 x 1A5EG (these are on a sticker pasted inside the cab). The Radio is a A/B Battery only tabletop set with a band switch for SW/BC. All tubes are present (but are G/GT) and filament pins 2,7 on all tubes show a few ohms continuity. I do not have a tube tester.
I think this set may be a 1942 48T but I'm not sure. It looks EXACTLY like image of the 48T on this forums website under "philco in canada"
I traced back the A+ and A- from the tubes to the on/off switch then to a 2 prong plug on the power cable.
I traced back B+ and B-, it seems to be wired for 2 x 45 volt batts in series and a separate 1.5v batt.
I powered it up.
Nothing. Filament Voltage drops to 1.2v. Caps are all original, I'll recap the papers and try again. Since they are all original, I'm thinking re-stuff the paper tubes?
Has anyone seen one of these Radios before? Or a schematic? I can post pics if required.
-Ritchie.
(This post was last modified: 04-28-2015, 01:30 PM by Ritchie.)
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Hi Ritchie, Welcome to the Phorum!!!
Sure a picture would be helpful, here's the "How to add pictures" link.
Interesting that the list of Canadian sets on this web site shows the 48T as an AC set, perhaps Ron or Arran will have a thought on this one.
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Hi Richie & Welcome
I don't have a diagram for your set but may not need one. Just for grins with the set off take your ohm meter measure the resistance from pin 3 of one of the 1A5 to pin 3 of the other 1A5. Should show around 300 to maybe 1000 ohms
GL
Terry
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(03-10-2015, 03:47 PM)Radioroslyn Wrote: Hi Richie & Welcome
I don't have a diagram for your set but may not need one. Just for grins with the set off take your ohm meter measure the resistance from pin 3 of one of the 1A5 to pin 3 of the other 1A5. Should show around 300 to maybe 1000 ohms
GL
Terry Thanks Terry,
Reading is just over 300. These pins go to the left/right primary winding of the Output Trans.
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Ok check to see if you have HV on those pin with the set on. Also disconnect one side of the speaker measure the resistance of the spk v.c. and the secondary of the output transformer.
Terry
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The audio trans secondary is 0.6R. The speaker measures 3.8R I cant measure HV as I've pulled some caps etc out in prep for a cap job. The Audio trans seems a little low?
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I think the transformer is ok. Reconnect the spkr to the transformer. Take a 9v battery connect one to the pri of the transformer. Take the other side of the battery just touch it monetarily to the pri lead. should hear a pop in the spkr The only reason I want to test out the trans is it a common problem.
You also may want to give your off/on switch a shot of Deoxit. It controls the filament and HV.
Terry
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I think it was the HV I measured when I first turned it on to make sure I had the power right. The pins were +89v on the 1A5's and then dropped alarmingly to ~68 on the 1H5(pin3) I turned it off at that point.
Just connected the speaker back up, large pop when I quickly tap the 9V battery on the primary's.
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Looks like a Philco 42-321 compact table top model (1942)
Not the right schematic though
48T from canada has wrong tube line up too
Belmont 551 has this chassis but knobs dont meet up
http://www.nostalgiaair.org/PagesByModel...002133.pdf
Times I have been electrocuted in 2021
As of 1/01/2021
AC: 4 DC: 1
Last year: 6
(This post was last modified: 03-10-2015, 08:17 PM by OldRestorer.)
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I would think that 68v is about right. On pin 3 of the 1H5 there should be a high value resistor for the plate load. What you are seeing is the drop. Do you hear a buzzing sound when you touch the grid cap of the 1H5??
Hi Kirk It may look like but it's an AC/DC set not a battery job. TNX for having a look.
Terry
(This post was last modified: 03-10-2015, 08:20 PM by Radioroslyn.)
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No sound at all. no hiss, static, pop or squeal. It was completely quiet.
Yes, there is a resistor between B+ and 1H5G pin 3. its in circuit measurement is 1M ohm brown body with a black end stripe and green middle stripe.
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Do you see any glow from the filaments? There going to be pretty dim but visible in a dark room.
Terry
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Yes, they glow. just appear as very dim orange lines in the dark.
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Having poured through lots of schematics, my radio matches up quite well with the main parts of a 41-95 some cap values are off but cap locations and resistor values are correct. the 41-95 does not look like it has a band switch though.
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