The following link will get you a searchable PDF copy that is "only"
36MB and includes the supplement, after the index.
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The big problem with this book is that there is just so much information
packed between the covers, it is hard to find helpful information in a
timely manner.? Like any good book, it turns into a time machine!? Now
searching for a keyword returns lots of hits which should make searching
for specific information so much easier.
Enjoy,
Jim

On Tue, May 28, 2024 at 06:37 AM, Jim Whartenby wrote:

John
The SX17 manual says that the measurements shown in the tube voltage
chart were made at a line voltage of 115 VAC.? That does not mean
that the SX-17 was designed for operation at 115 VAC, it just means
that the voltages measured are most likely within +/- 10% of the
values given in the chart at that line voltage.? Note too that the
voltmeter was specified at 1000 ohms per volt.? Modern DVMs have a
much higher input impedance so the voltages you measure will also be
higher then those listed in the chart.

Thanks. I got my information from a couple of online articles which
mentioned 110V as well as 117V, but I appreciate that mains voltages
vary and measurements vary depending on the instrument used. I am using
a DMM, but do occasionally check with an AVO 8 for comparison.

About the power transformer rating.? You should be able to calculate
the cathode current for most tubes in the SX-17.? The voltage given
for the cathode is listed in the tube voltage chart, the cathode
resistor value is given in the parts list.? Or one can just look in
your favorite tube manual for plate and screen currents at the plate
voltage given.? Same can be done for heater current for all tubes
except for the power rectifier.? When all of this is done you should
have a good idea of the requirements for the power transformer.

I thought about that? myself and will try and do some calculations. I am
curious about your exclusion of the rectifier from the heater current
calculation. It is obviously heated so must draw some current?

I may have a suitable power transformer here in Arkansas for the
cost of postage.
Regards,
Jim

That's a kind offer. I will do the calculations first and see what is
needed.
_._,_._,_

?

A few months ago I acquired a Hallicrafters SX17 receiver intending to restore it as a winter project. Well the winter months have come and gone and I have finally gotten around to getting it on the bench (without injury to self I might add - it is a bit of a boat-anchor!) for a preliminary look. This is my first time on here, so just wanted to say hello to everyone and thank the moderator for accepting me into the group.

As might be expected for something from circa 1937, the radio is in a bit dirty and metal surfaces are oxidized. Some of the wiring (particularly the mains) looks a bit of a mess and will require re-wiring, but the immediate showstopper is the fact that the power transformer (T7) has an open primary. There seems to be no indication on the radio of the mains input voltage, however, I have read that these were made to be powered from a 110Vac line? Since the radio is located in the UK, it may have been previously assumed that it would run from UK mains which is at 230Vac, which might perhaps explain the open transformer....

Can anyone confirm whether these were ever made for the UK market and for 240Vac mains supply?

The next question is whether it is possible to source a replacement? The manual I have found does not indicate the transformer voltages so I wondered whether anyone has this information?

This looks like it is going to be a huge project but I think it would be interesting to restore this circa 90 year old receiver if possible.