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Old March 5th 07, 03:26 AM posted to rec.radio.amateur.moderated
Mike Coslo Mike Coslo is offline
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First recorded activity by RadioBanter: Feb 2007
Posts: 168
Default Tube equipment question

wrote in
oups.com:
Some may tell you that all it takes to tune up a tube
transmitter is to "peak the grid and dip the plate", but
that's simply not correct. Tuneup procedures vary
according to rig design and you have to be specific.
Of course once you get the hang of it, the procedure
rapidly becomes second nature.


I enjoy twiddling knobs, kind of the same way I like a manual
transmission. 8^)


It's a question of skill vs. automation.


I've always wanted to know just what was going on in what I was
operating. I at least like the option betwen automatic operation and
manual. Skills can never hurt.


What specific hollowstate rigs are you considering?


* * Last year at Dayton I purchased a 40 and 80 meter Heathkit single
* * Bander as a learning tool - they are pretty simple. I restored
the * * 80 meter unit, and will start on the 40 meter one sometime.


I think you mean the Heath HW-12 and HW-22, or the later
A models of the same rigs.

They are from the early-to-mid 1960s, and have very limited
matching range. They are really only meant to match a 50
ohm load. Note that there isn't even a LOADING control on
them.


That would be the units with one exception. More on that later..


The Single Banders were Heath's answer to the "SSB is too
expensive" idea. Every possible simplification and economy
measure was used in them, yet the result is a usable 100 W
class SSB transceiver for one HF ham band.


The simplicity was what attracted me to them. No filters, nonotch,
no pbt, no RIT, no - well you get it.



Note that the
75 meter one stops at 3.8 MHz. Heath figured that by
simplifying the output pi network to the most extreme degree,
they could save a few dollars. Coming up with a 50 ohm
antenna was the ham's problem.


The 75 meter rig I have tunes to 4 MHz. It's also a HW22a, probably a
later mod. But all that simplicity is a good thing for a lad raised
mostly on integrated circuits! 8^)


I am now
* * looking at a Kenwood TS-830S. It's a hybrid, with tube finals. I
* * really like it so far, although I don't see it replacing my
IC-761.


That's a pretty good rig for its era. The matching range is limited
but it will handle 2:1 SWR without problems IMLE.


I have been pretty impressed so far. The receiver seems pretty hot,
certainly the sound is *good*. I'm listening to it right now, and it is
simply very legible. Tuning is only one speed, and a tad fast. Seems
strange just having SSB and CW, but overall I think I'll keep it.



I am hooked on computer control of the newer rig - sometimes!
Other times I just like that retro aspect.


One of the great things about amateur radio today is that we can
use a wide variety of technologies for the same or similar purposes.



I find it ironic that the evolution of the "state of the art" has come
full circle in about a half-century, at least in HF/MF:

- Ham rigs of the 1950s usually had wide range pi-nets which required
adjustment, but would match almost anything without an external
device.
- Ham rigs of the 1960s and 1970s usually had restricted-range
pi-nets which were easier to adjust, but sometimes required an
external matching device.
- Ham rigs of the 1980s and later usually have solid-state finals and
no adjustment - and usually require an external matching device.


And that is what I'm thinking about with regards to new rigs with
an internal tuner that has both balanced and unbalanced capabilities as a
natural evolution. There are a lot of Hams that don't have the ability to
put up towers and beams, and are looking at a wire antenna for a while. I
think its time for that

- 73 de Mike KB3EIA -