Hello Everybody,
I have an export version of a Fender Twin 65 RI power transformer (Export Version: #049181, US-Version #037610) The voltages of the secondary windings are 0-340 VAC - no CT, 0-6.3 VAC and 0-50 VAC.
Unfortunatly I can´t get any information about the maximum current rating of each secondary winding. Does anyone have more information ?
Thanks
Lars
Fender Twin 65 RI Power Transformer
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larsvictor
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Stevem
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Re: Fender Twin 65 RI Power Transformer
The re-issue amp uses a bridge recto, so yes it has no HV center tap and the 340 volts you measured makes for the 442 volts that the amp has when off the standby position .
If memory serves me right the stock Fender blackface and early silverface PTs have 465 ma on the HV winding and many of the better after market replacements have a tad over 500 ma.
The heater winding needs to have 6.2 amps and most that I have seen have 6.5.
The re-issue amp has about the same 62 volts on its bias winding as a non re-issue amp.
If memory serves me right the stock Fender blackface and early silverface PTs have 465 ma on the HV winding and many of the better after market replacements have a tad over 500 ma.
The heater winding needs to have 6.2 amps and most that I have seen have 6.5.
The re-issue amp has about the same 62 volts on its bias winding as a non re-issue amp.
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larsvictor
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Re: Fender Twin 65 RI Power Transformer
Thanks a lot. 500 mA should be enough for 4 6L6GCs and 7 12AX7. I want to use it for a Steel-String-Singer project (I know - wrong section here 
).
Lars
).Lars
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Stevem
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Re: Fender Twin 65 RI Power Transformer
Yup, I checked the stock Fender spec and 500 is 50ma more than stock!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Fender Twin 65 RI Power Transformer
Bear in mind that the ac current in the winding is 1.414 x more for a FWB than a bi-phase FW rectifier (in which the Iac = Idc), all else being equal.
Also, in theory, I think there may be lower winding loss, though it's tricky to balance that against the higher current / full cycle loss.
Also, in theory, I think there may be lower winding loss, though it's tricky to balance that against the higher current / full cycle loss.
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