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PA060 S Dynaco ST70 Upgrade Power Transformer Replacement MADE IN USA

For the connection diagram for this unit Click Here
Compare the height of the core to the one in your Dynaco!

Improved replacement power transformer for Dynaco ST70. Heavier construction, runs cooler, gives better regulation, won't buzz & hum like some originals do. Bolts in to ST70. No modifications required, wires have identical color coding as the original unit. Extra long telfon insulated (instead of cheaper PVC) leads.

Also could be used to make a 70-90W mono power amp (depending on output tubes & rectifier) using the MQ-451-CL output transformer. Secondary B+ winding is 720VCT (360-0-360) at 300 ma with 55V bias tap, plus two 6.3VCT 5 amps & one 5V 4 amp tube filament & rectifier windings, and 55V bias tap.. Can use solid state rectifiers or any single tube rectifier with filament up to 5V at 4 amps (or 2 5AR4/GZ34 could be used in parallel) & sufficient B+ current rating....usually, 5AR4 or 5U4. (note, watch that the voltage isn't above capacitor ratings if solid-state rectifier is used!) Primary 120VAC 50/60 Hz. Mounts in 2 5/8 by 3 1/2 inch (67 X 90 mm) hole, mounting bolt pattern is 3 X 3 3/4 inches (77 X 96 mm). Nice long teflon insulated leads.

A 240V 50Hz version of the PA-060-S (PA521) is also available (see below).

Using the PA-060-S to replace power transformers in other amplifiers... yes, it's possible, in amplifiers that need about 420-440V of B+ at from 150 to 250 ma, and the dimensions are similar to some other vintage amps (certain Scotts, at least). The problem in some Scott ,Fisher and other amplifiers is that you'd have to take the preamp filament supply off the 6.3V windings, wheras in most originals this came off the bias winding...the PA-060-S only has a bias *tap*, which will do fine supplying bias voltage, but won't support filament current.


PA521 ST70 Power Transformer for Dynaco 120v 240V Replacement for Dynaco MADE IN USAPA521 ST70 Power Transformer for Dynaco 120v 240V Replacement for Dynaco MADE IN USA

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