[claude.france]

Looking with more attention , after cleaning the rear side of the chassis , there is a ref number engraved on the iron:

" D91482 "  but nothing else .

no indication for the mains voltage 117 or 220 Volts ? so I suppose could be 117 , but 50 cycles for export ( Hertz )

[claude.france]

I checked my reading , could be I made wrong one , but not , the tube is really a 56 one .

Sure it has been put there when intervention manipulation , but wrongly by the operating people . Unfortunately , this kind of mistake can be often noticed in old radio sets .

[morzh]

http://www.radiomuseum.org/tubes/tube_56.html

This is what the 56 is.

Pin-wise it is the same as 37, but the Vf is 2.5V so it will either burn out, or take down the transformer's winding as it can withstand much more current and will draw way more current than the winding is capable of.

[Ron Ramirez]

As it is an export set, it was likely made for 220 volt, 50 cycle mains. Philco made lots of chassis in Philadelphia, USA, for export including sets intended for sale in the UK and Europe before they began producing chassis as well as cabinets in Perivale, Greenford, Middlesex in England.

[morzh]

As the only triode in the chassis, this 56, I suspect, could be the detector (diode connection) and was put there instead of 37, which is, what I think, should be there.

What do you think, Ron?

PS. Looking at the photo of the underchassis - yes, one could see how both the cathode and the plate are riveted to the chassis, so yes, it is the detector and should be 37.

[claude.france]

I Checked the heating circuit of all the lamps , none is cut .

S o I removed définitely the 56 of the chassis and will check in my stock , to get the rignt tube , if I have not , ill check to get one in the future many possibilities are offered to me .

Could be this 56 be put also there to " plug a hole " !

[morzh]

Well, before you even bother with replacing tubes, might as well go, check the transformer, then do the recap and, if needed, weed out bad resistors. Then if all is good, look for the tubes.
Oh, and do check the tubes before you use them.

[Ron Ramirez]

Claude

Before you jump into a repair job...

Please allow me time to look this up in the UK Radio Receivers DVD and see if it has something closer to what you actually have. I'm at work and cannot look now as the DVD is at home.

I will comment further on the tube (valve) layout at that time as well.

[Ron Ramirez]

Claude

I believe what you have is a model 223, not a 71.

You can find a schematic here (not very good quality but better than nothing):

https://elektrotanya.com/philco_271_222_...nload.html

There is also a partial schematic shown for versions with a phonograph pickup.

[claude.france]

really , indeed , no , not to plug a hole . but as a lamp replacement

I checked under the chassis .

in fact the 56 has been set there, I suppose ,  as replacement of the right lamp , but, we can say ,  correctly .

You can see on the followig photo, one of  the  6.3 V ring wire is not directly connected to the lamp socket , but via a small wired resistor on a steatite rod, so  placed there to absorb the 3.8 exceeded voltage .
you can see this resistor  beetwen the  two white " tassels " on the photos )  

It appeared that tis resistor is cut , not burned it seems , but just brocken .

If the radio was used innthat configuration , the limited consumption of this fitting limited the current of the 56 heating at normal valu , so 1 Amp , so only 700 mA more could be with the rignt lamp ,  instead of 2.5amp if the 56 were connected directly to the 6.3 Volt , so possibly not enough to overload the 6.3 V transformer output .

Perhaps also the 56 were under heated , using a resistor of more value il the calculation was made to maintain a 0.3 Amp consumption

[morzh]

Yeah, I was about to ask if there is some dropping resistor, but then I did not see it there, (given the size and the resolution of the photograph, though there was something there...whitish), plus it would need to dissipate quite a bit of heat (3.8W, that would require a 10W-capable resistor there, which is quite large) so I did not think they would do that.
They probably did not have a 37 so this is how they worked around the problem.
The sch shows 37, so I would restore the circuit to the original and buy the 37 tube.

[morzh]

Claude

I believe what you have is a model 223, not a 71.

You can find a schematic here (not very good quality but better than nothing):

https://elektrotanya.com/philco_271_222_...nload.html

There is also a partial schematic shown for versions with a phonograph pickup.

Ron

It shows 271 code 222.

[Ron Ramirez]

Read it again - the fine print next to the AC input on the schematic.

271
222
23 (by inference 223)

Let's take the USA equivalents as an example.

Model 22 - Model 71 chassis with phonograph
Model 23 - Model 91 chassis with phonograph

In Philco's model numbering scheme from 1932 until 1935 or so, a three digit model number beginning with the number 2 indicates an export chassis.

We know that model 23 is an American model with a 91 chassis.

We know Claude's cabinet is identical to a 23X, while the chassis has seven tubes, not nine.

We also know it must be an export set as American 71 sets do not have a long wave band.

I believe the schematic in the link I posted earlier matches Claude's chassis. So you can call it a 223 (which is my educated guess), 222 (which it is not since it looks nothing like a 22L), 271, or whatever you wish.

I'm sticking with 223 until I see proof otherwise.

You asked for my opinion in post #35. I have given it.

[claude.france]

Thanks a lot Morzh and Ron for schematics and infos , they will help a lot !  

here is the schematic extracted from your link

[Ron Ramirez]

As a followup, Claude...nothing like your radio is listed in the UK Radio Service DVD, so the schematic I posted a link to earlier will have to do, I believe. Hopefully it will help.