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"Universal series" Hammond PTs; New Sensor; Heyboer

4/2/2003 2:04 PM
"Universal series" Hammond PTs; New Sensor; Heyboer
The Hammond PTs' high current ratings are not the only reason why they produce higher voltages than they're supposed to. Hammond's regular pts only have a 115VAC input. With my 121-volt household ac, they give me voltages that are about 10% higher than what they're supposed to be - as if they really needed a 110 vac input.  
Hammond has a whole series of power transformers with a "universal primary." Each one has a bunch of taps on the primary, including a 120vac tap. That oughta keep the heater voltage within reason. They cost more than the comparable regular transformers, and they're a little bigger too.  
Why don't you just get the New Sensor 50-watt Marshall power transformer? Hoffman & Antique Electronic Supply sell it. I got a hunch that you can get it through the New Sensor website as well.  
Also, Heyboer's prices are very reasonable and their turnaround is fast. If they don't make a plexi repro power tranny, you can bet they make blackface bassman and tweed bassman power trannies.  
4/3/2003 2:30 AM
bob predaina Re: "Universal series" Hammond PTs; New Sensor; Heyboer
i'd have to agree with you that the 200 series Hammonds with their 115 VAC primaries aren't the best choices available -- the equivalent 300 series with the 120 VAC primary are a much better choice. the heater voltages are far more reasonable, and don't requrie tweaking to get the heater voltages into spec. the only downside is that they're significantly more expensive.  
one other OT to consider is the MM Plexi Repro. No significant price difference compared to the OEI Plexi if you get it on a group order. Another option is the newsensor OT. Dirt cheap, and a great transformer, regardless of its price.  

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