From: rohre (email@example.com)
Small world this!
Sunday Feb. 5 I was at the Georgetown (TX) hamfest and was visiting with Bruce
Williams of MXM Industries.
We lamented together the passing of several QRP kit making enterprises lately,
but Bruce has a number of stock units, and some with enclosures, so is
plugging away. He likely will be at the Manchaca Swapfest (Austin TX) April
I have constructed one of Bruce's 40 M transceivers as part of a community
school class I helped him put on, here in Austin. Each Saturday for a month
we met from 9 to noon, and he first gave the theory of the transceiver and
then assisted as the class each constructed their kit. Each one was given a
smoke test and tuneup and we got to view the very clean wave form on a scope.
(Bruce uses a modified IF can inductor to get this clean oscillator waveform).
In such a short time, with some class members needing my assistance in
learning how to solder, insert and trim components, etc., most got their
boards done, but unless they worked outside of class, did not get the
packaging into a cabinet done in class. You have to understand, most of the
class had never built anything, unless it was a crystal set from a plug
together Radio Shack "kit". However, even the first time solderers agreed
they had learned much and had a sense of accomplishment. I think we should
have had another coulple weeks if the class has a wide range of skill, or lack
Some noticed some interaction if they built the model that has the transmitter
on the same board with the receiver; and cured this by shielding.
Because Bruce also has that model as a separate transmitter and receiver
board, I think that would be the way to go giving the most flexibility in
packaging. I think some more instruction on layout rules in the instructions
might help newcomers. But the kits are not just "a bag of parts"
With so many (15) kits going all at once, a few swapped values in parts
caused us to take about a week to get everyone the complete set of parts. We
were doing this each weekend in Austin, and Bruce lives east in Smithville,
perhaps an hour drive from class, so the logistical supply line inevitably got
stretched a bit! You learn a lot putting on a class like this for the first
time, and we would bring more spare parts next time!
As stated, you do have to normally furnish your own box, and jacks and
switches. For the first time constructor, this presents the need for an elmer
to guide one to not make power and other jacks the same, leading to
accidental and problem hookups.
You can buy an nice knob and gear reduction cap from Bruce, and it is one of
the smaller ones for the range, and is highly reccommended.
Bruce had his kits reviewed in 73 magazine, although the VFO model may not
have been as yet. The kit I built is rockbound transmit, with the usual
receive arrangement. There is a VFO model.
The oscillator and receiver sections utilize the Toko type 10.7 IF cans. With
the cap cut loose on bottom, you can go up to 14 Mhz; or with extra parallel
caps you get 7 Mhz, etc. That cuts down on the toroid winding chores; which
if memory serves me right left only two, the driver transformer and the output
I was just a club officer facilitating a group who wanted to get exposed to
QRP from the local general interest ham club, and do not work for Bruce or
MXM. Bruce has been around the ham business awhile having worked for the
founder of Swan and Atlas radio. I met Bruce through my interest in
collecting the old models of Atlas transceivers. He will make his radios work
if you have a problem. He demos at local swapmeets by having a helical whip
pair mounted as vertical dipoles on a pvc pole in a coffee can of concrete
with a coax run in to his rigs. They have plenty of speaker volume and can be
heard around the swapfest room.
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