Valve-operated Fonadek telephone amplifier
 

In this long-closed thread from 2014 I commented:
Well, I did acquire a valve version at a Telephone Heritage Group event last month. The HT+ battery lead was detached on acquisition, but with a combination of inspecting soldering for traces of possible broken-off wire-ends and help from @Keithinuk I managed to establish that it connects to g2 of a beam tetrode valve!

Having now stocked up with cheapo PP3 batteries from Poundworld, I connected seven in series to approximate the 67½V HT of the original B114 battery and a "C" cell for the 1½V LT. It now nicely amplifies the sound from the receiver of a 332 telephone's handset.

Re: Valve-operated Fonadek telephone amplifier
 

That sounds fun. Could we have a picture, Dave?

Re: Valve-operated Fonadek telephone amplifier
 

Not particularly photogenic, but here we go:

Re: Valve-operated Fonadek telephone amplifier
 

I sold one of those through the forums donkey's years ago. I wonder if it's the same one?

Re: Valve-operated Fonadek telephone amplifier
 

I like it, Dave, though its wife-acceptance-factor is surely low! I bet there are not too many of those which have survived.

Re: Valve-operated Fonadek telephone amplifier
 

I picked a virtually mint transistorised version that operates off a single PP3 a year or two ago. Great when demonstration CNet using a 2XX/3XX phone. They do pop up on eBay from time to time.

Re: Valve-operated Fonadek telephone amplifier
 

Maybe correct, I only have the transistorised version.

Crossed with P

John.

Re: Valve-operated Fonadek telephone amplifier
 

I had the transistorised version about 30 years ago which was being chucked out in an office clearout where my aunt worked. Sad to say that I converted it into an intercom, and now its long gone. It looked early-mid 1970s vintage and had a "Pansonic" (sic) speaker.

Re: Valve-operated Fonadek telephone amplifier
 

I bought this one from Max Flemmich, who runs a telephone museum near Kilmarnock, so probably not. Do you recognise any of the scuffs etc?

But then, I don't have one of those in my collection - wife, that is!

I also have the transistor version, along with a later transistor variant:

Re: Valve-operated Fonadek telephone amplifier
 

Ah yes, mine was the "later" version which you've pictured. I'd forgotten about the rather nice royal crests, which were intact on mine. Have a look inside the speaker housing to see what's fitted...

I could never work out what the preset pot accessible under the volume knob was for.

N.

Re: Valve-operated Fonadek telephone amplifier
 

What's fitted inside the speaker housing of the later one is a replacement from (if I recall) a transistor radio, as the one it came with was O/C.

What, in particular, were you wanting me to look for?

I don't know what the preset is for, either, but there is one at the rear of the earlier tranny version, and also one inside the valve unit (though only accessible by removing the back cover).

Re: Valve-operated Fonadek telephone amplifier
 

I just wondered if it had the same blatant Panasonic rip-off "Pansonic" speaker fitted that mine did :)

Re: Valve-operated Fonadek telephone amplifier
 

I may still have the original (dead) 'speaker somewhere, but don't hold your breath. I'll report back if I find it.

Re: Valve-operated Fonadek telephone amplifier
 

Good to hear is all working, I may give it a go myself.
My one has a tab that rotates the mic, why?

Re: Valve-operated Fonadek telephone amplifier
 

Maybe they found that the pickup works better in a different orientation for different receivers.

I must say yours looks in very fine condition - apart from the single supporter for the heraldic shield looking a little lonely. :-)

Re: Valve-operated Fonadek telephone amplifier
 

Perhaps it helps a little with background noise?
Alternatively, is it a microphone or an inductive pickup?

Re: Valve-operated Fonadek telephone amplifier
 

It's the latter - which is why I always refer to it as a pickup rather than as a microphone.

Background noise would be introduced via the mechanical focusing of sound into the transmitter of the handset - which is how that part of the hands-free operation works.

Re: Valve-operated Fonadek telephone amplifier
 

I've seen that version before, but this one is a new one on me. (Photo from Ebay).