1. Refurbished Eico ST-70 Output Transformer S-32021-1. Repainted bells and new hardware. $80.
2. Custom Eico HF87/89 transformers, $49 each.
I bought two custom Eico HF87/89 Power Transformers (PN 30031) from Heyboer in 2005, back when our mains voltage was 125.
I installed both in different builds and noticed that the output voltages were low -- 5.75 on the filaments and about 162 on the HV (this transformer was intended for a voltage-doubling circuit). When I measured the linenow, it's about 120, which explains why.
These can be used as is in a higher line voltage application.
Alternately, you can add an inexpensive 6.3V filament transformer in "boost" configuration and get closer to the spec's, which are (according to SAMS):
170V @ 0.9A
6.3V @ 7.6A
75V for bias
Where I could, I spliced back the leads that I cut. The transformers were otherwise not used after initial installation.
2. Custom Eico HF87/89 transformers, $49 each.
I bought two custom Eico HF87/89 Power Transformers (PN 30031) from Heyboer in 2005, back when our mains voltage was 125.
I installed both in different builds and noticed that the output voltages were low -- 5.75 on the filaments and about 162 on the HV (this transformer was intended for a voltage-doubling circuit). When I measured the linenow, it's about 120, which explains why.
These can be used as is in a higher line voltage application.
Alternately, you can add an inexpensive 6.3V filament transformer in "boost" configuration and get closer to the spec's, which are (according to SAMS):
170V @ 0.9A
6.3V @ 7.6A
75V for bias
Where I could, I spliced back the leads that I cut. The transformers were otherwise not used after initial installation.
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