For sale are Bud's Purvine used 5k SE trans for 45/300B amps. He never specified the current but said up to 80 mA is "doable". I only ran it in 45 amp so around 40 mA. Was going to make a Reichert amp with them but nah... $245
Push Pull interstages were supposedly built for Lynn Olson ballanced amps. . two primaries , two secondaries and suitable for variety of tubes . No DC on primary. never used. $200. Pictures later
Push Pull interstages were supposedly built for Lynn Olson ballanced amps. . two primaries , two secondaries and suitable for variety of tubes . No DC on primary. never used. $200. Pictures later
Opt trans size is 3.75"L x 3.5"D x 3.25"H. Leads length between 5-6" .Mounting hole distance 3.25" L x 2.375" D (3/8"). These are medium/big sized trans.
I will dig out interstage transformers which are similar sized if anyone express interest They are NOS so have full sized leads .
I will dig out interstage transformers which are similar sized if anyone express interest They are NOS so have full sized leads .
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What Bud Purvine wrote about the interstage transformers ;
Looks like you have the Karna #1 IT. This is good for 145 vac RMS drive voltage @ 20 Hz and is used to drive either 2A3 or 45 tubes, from an EC99. Most driver tubes should work well with the transformers, mu favorites being the 7199 in PP parallel, into this same transformer. You have huge amounts of current capability here and so long as you don't exceed about 170 vac RMS drive voltage you should be fine.
.Do note that these devices have a rising high frequency centered at about 35k Hz and do need to have a substantial load place on them to achieve flat response. Also note that they are pretty much immune to input load variations.
Looks like you have the Karna #1 IT. This is good for 145 vac RMS drive voltage @ 20 Hz and is used to drive either 2A3 or 45 tubes, from an EC99. Most driver tubes should work well with the transformers, mu favorites being the 7199 in PP parallel, into this same transformer. You have huge amounts of current capability here and so long as you don't exceed about 170 vac RMS drive voltage you should be fine.
.Do note that these devices have a rising high frequency centered at about 35k Hz and do need to have a substantial load place on them to achieve flat response. Also note that they are pretty much immune to input load variations.
Each transformer weights around 7.5 lbs and has 4, 8 , 16 ohm taps . Primary nominal 5 kOhm .Current up to 80 mA according to Bud's words . No ultralinear taps. These are the first transformers from the SE batch coming from Onetics.
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OPTS are sold to Steve. NOS PP interstage transformers are still for sale.
.."Looks like you have the Karna #1 IT. This is good for 145 vac RMS drive voltage @ 20 Hz and is used to drive either 2A3 or 45 tubes, from an EC99. Most driver tubes should work well with the transformers, mu favorites being the 7199 in PP parallel, into this same transformer. You have huge amounts of current capability here and so long as you don't exceed about 170 vac RMS drive voltage you should be fine.
.Do note that these devices have a rising high frequency centered at about 35k Hz and do need to have a substantial load place on them to achieve flat response. Also note that they are pretty much immune to input load variation"..
.."Looks like you have the Karna #1 IT. This is good for 145 vac RMS drive voltage @ 20 Hz and is used to drive either 2A3 or 45 tubes, from an EC99. Most driver tubes should work well with the transformers, mu favorites being the 7199 in PP parallel, into this same transformer. You have huge amounts of current capability here and so long as you don't exceed about 170 vac RMS drive voltage you should be fine.
.Do note that these devices have a rising high frequency centered at about 35k Hz and do need to have a substantial load place on them to achieve flat response. Also note that they are pretty much immune to input load variation"..
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