Yacht folk remember these drum servos.
Adverts in old magazines or a post or email to model yacht forums might be enough to get an answer but a
photo or two would help.
It's likely the same voltage the receiver can withstand
if it does not have a separate battery lead.
With battery lead, nominally 7.2 or 8.4 battery, with the load that burns drive transistors being more significant.
I think the broken one that I have is from them.
The current rating is a tiny 800mA from bipolar BC338, BC328 transistors compared to the robust 21st century semiconductors in a £4, 6kgcm standard size servo. The drive transistors would burn out where a servo motor would burn out today.
I hesitate to write this as the the supplier is long gone and
SLM won't be able to help. They don't keep anything but injection moulded boxes.Before the internet SLM had a stapled paper RC related catalog but concentrate on the boxes to business customers
My servo came as a drum servo mechanism from W.E.SLM, who supplied Fleet Systems metal & injection moulded plastic parts, supplied mechanics to W.E..World and others fitted their servo circuit boards in different connector options.
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