valve chain voltage

1/13/2010 9:36:30 AMfrank goddard

The design voltage to this tube chain is 62 volts. I have a transformer that can give 55 volts. Do you think there would be noticeable performance problems with this set operating at 7 volts below par,

many thanks. Frank Goddard Doncaster England.

1/13/2010 11:14:19 AMNorm Leal

Frank

With strong tubes the radio will work but take a little longer to start operating. Tubes with good emission will operate just as well on this reduced voltage.

Norm

: The design voltage to this tube chain is 62 volts. I have a transformer that can give 55 volts. Do you think there would be noticeable performance problems with this set operating at 7 volts below par,
:
:many thanks. Frank Goddard Doncaster England.
:

1/13/2010 12:31:04 PMEdd

Sir Frank. . . . . .

I have always wondered about your situation, with you quite frequently being involved with 120 VAC sets, even with your presence in England, being indicitive of your having 220 from the "mains" .

Of course, you seen to come up with battery powered sets from time to time also . . . .

Therefore, visualising you with having one "well used" isolation / dropper 220/110 transfomer used to test out or operate those 120 V receivers that you have.

With the current situation of potentially having that 6 volt of voltage deficiency, it would be distributed AMONGST the tubes and actually not be horrific.

Expecting only a subtle drop in max volume capability, and the RF situation being most affective of the mixer osc tube on high SW frequencies IF even being present on this set.

An equal situation, which we seem to experience "over the pond" from you, is the situation over here of having a set that was designed for lower AC line voltage and we need to DECREASE the voltage about that equal amount.

Soooooo why don't you do the inverse of what we usually do . . . that being done by taking a 6.3 V filament transformer and wiring its primary across the input AC voltage and then its isolated secondary winding will be creating an extra 6.3 volts for you to wire series AIDING into that supply chain and bring you up to ~1 volt of what you wanted.

Even the lowest rated filament transformer should be fine, as I think that the very smallest ones I encounter are usually 1 amp, which would be 3x of the 300 ma requirement used by your filament string.

HOOKUP:

73's de Edd

:Frank
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: With strong tubes the radio will work but take a little longer to start operating. Tubes with good emission will operate just as well on this reduced voltage.
:
:Norm
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:
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:: The design voltage to this tube chain is 62 volts. I have a transformer that can give 55 volts. Do you think there would be noticeable performance problems with this set operating at 7 volts below par,
::
::many thanks. Frank Goddard Doncaster England.
::
:

1/13/2010 4:09:41 PMfrank goddard

Thanks to you both. As usual perfect , concise information and help.

Edd/ I have some 200 radios in my collection. All USA models. When a young lad my Dad started me along the radio route. It is not my job but just a passion. I have been to the USA some 30 times and always bring back home a few sets - even posting some in advance. I am going to PA in May and will take a day trip to Kutztown for the Radio Show before going on to Gettsurgh,

Frank

1/13/2010 4:22:22 PMThomas Dermody

You know, what you could also do is gather all of the sets with the same tube types and current draw, and wire them in series, running two at a time. The tandem radio sets would work well from 220 volts.

...I am half joking, by the way.

1/14/2010 1:18:17 PMfrank goddard

Thanks Thomas. Suppose I could tandem 4 together and use the 440 volt supply that runs up the street too.

To add also to my prev' post - millions of radio sets were imported from the USA to the UK during WW2 since factories here were busy with war work. Many of these survived ( mostly AA5 types) and it was these in particular and there very special cabinet design and inovation that cought my Dads interest - and by default mine also.

Frank

:You know, what you could also do is gather all of the sets with the same tube types and current draw, and wire them in series, running two at a time. The tandem radio sets would work well from 220 volts.
:
:...I am half joking, by the way.
: