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Vintage Telephony and Telecomms Vintage Telephones, Telephony and Telecomms Equipment |
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19th May 2017, 7:37 am | #1 | |
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Valve-operated Fonadek telephone amplifier
In this long-closed thread from 2014 I commented:
Quote:
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.
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19th May 2017, 8:04 am | #2 |
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Re: Valve-operated Fonadek telephone amplifier
That sounds fun. Could we have a picture, Dave?
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19th May 2017, 9:36 am | #3 |
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Re: Valve-operated Fonadek telephone amplifier
Not particularly photogenic, but here we go:
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19th May 2017, 9:41 am | #4 |
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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?
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19th May 2017, 9:42 am | #5 |
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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.
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19th May 2017, 10:19 am | #6 |
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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.
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19th May 2017, 10:21 am | #7 | |
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Re: Valve-operated Fonadek telephone amplifier
Quote:
Crossed with P John. |
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19th May 2017, 11:47 am | #8 |
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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.
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19th May 2017, 11:49 am | #9 | |
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Re: Valve-operated Fonadek telephone amplifier
Quote:
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:
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19th May 2017, 11:51 am | #10 |
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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. |
19th May 2017, 12:02 pm | #11 |
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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).
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19th May 2017, 1:15 pm | #12 |
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Re: Valve-operated Fonadek telephone amplifier
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19th May 2017, 1:48 pm | #13 |
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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.
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19th May 2017, 2:07 pm | #14 |
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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? |
19th May 2017, 4:46 pm | #15 |
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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.
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19th May 2017, 8:28 pm | #16 |
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Re: Valve-operated Fonadek telephone amplifier
Perhaps it helps a little with background noise?
Alternatively, is it a microphone or an inductive pickup? |
20th May 2017, 7:47 am | #17 |
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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.
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20th May 2017, 9:09 pm | #18 | |
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Re: Valve-operated Fonadek telephone amplifier
Quote:
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