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Help - tube radio

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I got an old "Pilot" tube radio from a friend and want to know the following:
1) Where can I find a circiut for it?
2) What are the functions of selectors 1...6?
3) What impedance speaker can I connect to it?
4) What are the functions of connectors A...D?

Thanx for all help.

Here follow pic's of it:
 

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Rear:
What I also want to know is how to identify a tube with no markings? Tube ECH81 broke when I touched it, it was all white inside. Now I got a bag of old tubes, but some do not have any markings. There is 1 that look exactly the same , can I try it in this place?

Rear:
 

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The "valve with no markings" probably has got markings, underneath the screening sleeve, (it comes off). It is probably an ECC85 double triode, used as an FM tuner head, though I can't locate a detector.

Connectors, (first thoughts):

A: Aerial (antenna) and earth (ground). This is for AM.
B: Signal input from record (phono) deck.
C: Looks like HT (+B), and heater power for another unit.
D: Mains power for record deck.

The ECH81 has no subsitutes that I know of, other than (probably) a US equivalent number. I can't access info at present.
It is used as an oscillator (triodes section), and mixer (heptode section).

The EBF89 is used as IF amplifier and detector.

The ECL86 is the audio amplifier.

The EZ81 is the rectifier.

Send me some biltong if I'm right;)
 
If the Valve is a Mullard / Philips / Valvo...

...it should have a small etch marking which will tell you the type number , year (not which decade) and factory it where it was produced . The first digits tell you the type number . Can you take a look and I'll check my list ?

316a
 
dhaen said:
The "valve with no markings" probably has got markings, underneath the screening sleeve, (it comes off). It is probably an ECC85 double triode, used as an FM tuner head, though I can't locate a detector....

Send me some biltong if I'm right;)


Thanx for info John
Any idea where I will connect poweramp or speaker on this unit?
 
dhaen said:
Hi Baz,

I could be wrong about connector D.
Trace the 2 wires from the output transformer, the one in the middle next to the tuning cap. They should come out on a connector; maybe D.

Cheers,


The wires from the little transformer goes to connector C. Is this then for a speaker?
What impedance speaker will be O.K?
I have no experiance with tubes, so please excuse simple questions. :)
 
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Joined 2003
FM?

Are you sure it's FM capable?

There's only one tuning capacitor that I can see, and it would only be suitable from LW/MW/SW. To be able to tune VHF/FM, it needs a much smaller set of vanes of the variable capacitor, or perhaps slug tuning. Can we have a detail shot of the tuning capacitor? (It's the big vaned lump with the pulley and string.)
 
Hi John,

There's probably no way of determining the speaker impedance, but I would guess at 4 ohms. 8 ohms would be fine too, but the power output would then be less.

I would have thought that a late fifties early sixties radio was most likely to be 15 or 16 ohms for an external speaker?

From memory, most of the ones of that vintage I worked on were that with some 12 ohm and some 8 ohm.

I saw very few 4 ohm until mid to late sixties...

maybe my memories wrong... what do you think?

James
 
Re: FM?

EC8010 said:
Are you sure it's FM capable?

There's only one tuning capacitor that I can see, and it would only be suitable from LW/MW/SW. To be able to tune VHF/FM, it needs a much smaller set of vanes of the variable capacitor, or perhaps slug tuning. Can we have a detail shot of the tuning capacitor? (It's the big vaned lump with the pulley and string.)

I'am back. Here is another pic. The thingy behind the valve (is it valve or tube?) got 2 pieces on 1 shaft that can move upo and down.
 

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