Pilot H665 radio.

[Dick Glennon]

Hi again, I have a Pilot radio I would like to restore, but I have no output transformer or 6U5 Magic Eye. Is the transformer a special to suit the 6F6 output valve or could I use one from a different chassis? Would it be possible to get an EM34 to work instead of the 6U5 (different base)?

Thanks again, Dick.

[vinrads]

Looks like you need a tx with a 7k ohm primary for a 6f6 , depending on the speaker ohms , do you have any transformers , or are looking for one , Mick.

[Dick Glennon]

Hi again, In replying to your question, presently I do not have an output transformer or a speaker but I see that the 6f6 can be replaced with a 6v6. I may have a chassis that would have had a 6v6 output valve. Could the output transformer and speaker from that chassis be installed in the H665.

Thanks again Dick

[Diniz Diniz]

Originally Posted by Dick Glennon

Hi again, I have a Pilot radio I would like to restore, but I have no output transformer or 6U5 Magic Eye. Is the transformer a special to suit the 6F6 output valve or could I use one from a different chassis? Would it be possible to get an EM34 to work instead of the 6U5 (different base)?

Hope someone comment on that, since I have the opposite problem...I have two 6U5 but my sets only use EM34... I don't know if it is possible "convert" them with some rewire work.

Cheers.

[Herald1360]

Yes, if the transformer physically fits. The 6V6 will drop straight in though for optimum performance you might want to tweak the cathode bias resistor.

[Dick Glennon]

Hi again, The symbols on the 665 pilot schematic seem to be early American, has anyone come across a translation to the later symbols, pin outs etc. It would be very reassuring if such were available. Also does the dim bulb always light when in circuit. Thanks again Dick.

[ms660]

Originally Posted by Dick Glennon

Hi again, The symbols on the 665 pilot schematic seem to be early American, has anyone come across a translation to the later symbols, pin outs etc. It would be very reassuring if such were available.

Schematic....6K8....Top to bottom:

Mixer anode (a) Pin 3.
Mixer screen grids (g2&g4) Pin 4.
Oscillator anode (at) Pin 6.
Oscillator grid & mixers oscillator injection grid (gt&g1) Pin 5.
Mixer signal grid (g3) Top Cap.
Cathode (k) Pin 8.


Heater (Not shown) Pins 2&7.

Metal shell, pin 1.


6U5....Top to bottom:

Target (t) Pin 4.
Triode anode (a) Pin 2.
Triode grid (g1) Pin 3.
Cathode (k) Pin 5.


Heater (Not shown) Pins 1&6.


6Q7G....Upper left:

Diode anodes (a(d1)&a(d2)) Pins 5&4 (Connected together in schematic)

Bottom left:

Cathode (k) Pin 8.

Next right:

Grid (g1) Top cap.

Next right:

Anode (a) Pin 3.


Heater (Not shown) Pins 2&7.

------------------------------------------------------------------------

The other valves should be self explanatory, pin connection data can be found here:

https://frank.pocnet.net/

Lawrence.

[Dick Glennon]

Hi, Thank you Laurence for that information, very much appreciated. One other question? There are two shielded capacitors 0.01 each in the one can on the mains coming in. What could I use in modern caps in place? Regards Dick.

[ms660]

Originally Posted by Dick Glennon

Hi, Thank you Laurence for that information, very much appreciated. One other question? There are two shielded capacitors 0.01 each in the one can on the mains coming in. What could I use in modern caps in place? Regards Dick.

Replace them with 0.01uf, Y Class type capacitors only.

Lawrence.

[Dick Glennon]

Hi again, I am still not sure of the the PIN numbers on the valves. I have included the schematic of the valves but I am not sure of the symbols. Ihave also done a drawing of the valves with letters on the symbols. If ye could put a number to each letter it would be great. Example-: F 6K8=8 etc. Thanks again, Dick.
Sorry I meant to attach as 2 images but my iPad won't let me attach 2 separate images

[ms660]

6K8:

A = Pin 3 (a)
B = Pin 4 (g2,g4)
C = Pin 6 (at)
D=Pin 5 (gt,g1)
E = TC (g3)
F = Pin 8 (k)

6K7:

A = Pin 3 (a)
B = Pin 5 (g3)
C = Pin 4 (g2)
E = TC (g1)
F = Pin 8 (k)

6Q7:

A = Pin 3 (a)
B = TC (g)
E = Pins 4&5 (a(d2) a(d1))
F = Pin 8 (k)

6F6:

A = Pin 3 (a)
B = Pin 4 (g2)
E = Pin 5 (g1)
F = Pin 8 (k,g3)

Lawrence.

[unitelex]

Originally Posted by ms660

Replace them with 0.01uf, Y Class type capacitors only.

Lawrence.

https://uk.farnell.com/w/c/passive-c...2&sort=P_PRICE

I have used the KEMET class Y2 from Farnell in the past, had no issues.
Best Regards
Chris

[Dick Glennon]

Hi again, thanks for all the help as always, very much appreciated. Regards, Dick.

[Dick Glennon]

Hi again, I still have not got a transformer/speaker to suit the h665. I do have transformers/speakers from other sets and I was hoping that ye might be able to advise m as to what other output valves would be compatable with the 6f6/6v6.I know which transformer is for which output valve. I would only like to get it working if not perfect. The cabinets were beyond repair (all wooden). Regards, Dick.

[Ed_Dinning]

Hi Dick, for a proving test virtually any op transformer will do and don't turn the volume right up.
If you get it running mail me and I'll see if I can find something suitable (very busy atr present)

Ed

[Dick Glennon]

Hi again, I have an op transformer from a PYE 15A. It has got just four wires, two primary and two outputs with a third output not used. I have four wires coming to the connector which would have connected to the original output transformer/speaker. I have included a picture of what I am trying to do.This is only for testing purposes. Any help would be very much appreciated. Regards, Dick.

[ms660]

Pins 1&2 to A&B (any way round)

Pins 3&4 to a 1.2k 10 Watt resistor.

D&E to a suitable loudspeaker.

Lawrence.

[Dick Glennon]

Hi Lawrence, Do pins 3&4 join the resistor at one end and does it then go to chassis?, Thanks again Dick.

[ms660]

One end of the resistor connected to pin 3, the other end of the resistor connected to pin 4 so that it's in series with the HT feed to the rest of the circuit, it's to replicate the resistance of the missing loudspeakers field coil.

Lawrence.