(Bob Monaghan) wrote in message ...
I suspect we old-timers are wrong in believing that more radios were
designed or made in the past than today, probably by factors of 500% or
more. The main reason is QRP radios using modern ICs for the receivers and
MOSFET transmitters, coupled with a revival of nostalgia tube simple
transmitters.

Some snipped to save space

Bob, a very well reasoned and written response to the original posting
- I can only concur. What seems to be forgotten is that amateur radio
has only ever been a hobby appealing to a small minority of
technically inclined people - the same numbers are still there, but
with the ready availability of store bought radios, the numbers seem
even smaller. A cursory search of the net reveals many people doing
many interesting things.

If we keep canning each other with "Yor only a CBer" type labels, then
yes indeed, things are grim - things will NEVER be as good as the "old
days" -thats why we call it nostalgia, and your points about using
surplus ww2 junk etc are correct - that wasnt homebrew, it was
adaption of existing equipment.

There is SO much stuff out there that can be modified/adapted to ham
use - junked computer UPS supplies provide a BIG 18v power transformer
for a homebrew linear supply, ex computer switchmode supplies are easy
to mod to 12v at 20 amps plus.

Perhaps the problem is lack of lateral thinking - one thing is for
sure, as long as we continue to argue and bitch and denigrate amongst
ourselves, how can we expect (or even deserve) continued free access
to the radio spectrum we are licensed to use!

73 de VK3BFA Andrew.

yes, Andrew, thanks for that note and some very good points...

we recently had our annual regional Hamcom 2004 convention, at which I had
the chance to catch local microwave and antennas guru Kent Britain's
WA5VJB's seminar on microwaves modifications. My favorite was a obsolete
cell phone 3 watt output chip that does 18 watts nicely on 13.8 Vdc ;-)
All the wi-fi and garage door conversions into microwave transceivers, and
the police radar detectors into microwave setups. And how about some of
the simple conversions of TV tuners into spectrum analyzer projects? ;-)
And the cable TV modules that do all sorts of jobs from preamps to power
amps ;-) So I just joined the North Tx Microwave Society to expand beyond
the satellite and ATV stuff we are doing now into new areas for our club
;-)

so thanks to computer and phone co. surplus, we may have a second
generation of surplus conversions to rival those of the 1950s and 1960s
for military surplus to amateur radio uses?

grins bobm

--
************************************************** *********************
* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
********************Standard Disclaimers Apply*************************

On 11 Sep 2004 23:31:06 -0500, (Bob Monaghan)
wrote:

we recently had our annual regional Hamcom 2004 convention, at which I had
the chance to catch local microwave and antennas guru Kent Britain's
WA5VJB's seminar on microwaves modifications. My favorite was a obsolete
cell phone 3 watt output chip that does 18 watts nicely on 13.8 Vdc ;-)

You got a part number for that chip, Bob?
--

"What is now proved was once only imagin'd." - William Blake, 1793.

nope, sorry, but it was a more or less typical example of some of Kent
Britain's and others discoveries of easy ways to get onto microwave bands.
Raising the voltage on these chips does great things to the power output,
as that E^2/R goes up fast as E goes up a little ;-)

Another example was an amplifier with many microwave modules, most of the
power was used to produce a linear (digital compatible) output; junk that
overhead, and the power went up from 10 watts or so to over 100 watts ;-)

You might try emailing the North Texas Microwave Society or Kent directly?
http://www.ntms.org/ - we are having a major conference in October I
hope to attend, so I may have more notes there ;-) Kent is also the
author of the "cheap yagi" designs from VHF-CQ and other online sources.

sadly, there was a second seminar at Hamcom 2004 on resources for
microwave wanna-bees. The first were a series of older books on microwaves
and test equipment, with the sensible observation that most of the
affordable test gear being surplused now is described in use in these
older books ;-) The second was a series of newsletters and publications,
some in German/English, from RSGB, and ARRL on microwaves operations etc.

Some of these were described and seen to be quite pricey for the amount of
articles therein ;-( The NTMS has evidently made an effort to build up a
collection of articles and resources related to microwaves, rather than
have each member try to duplicate these costly and hard to find
references.

I am not seeing a lot in the way of homebrew microwave construction or
conversion articles, given some of the relatively easy projects I have
seen described at these seminars and in some ARRL materials I have etc.?
So the conference may turn up some more resources, I hope ;-)

Part of the motivation here is we are trying to "inherit" some big
roof-top microwave satellite dishes from our engineering school as these
get obsoleted as we go online with streaming video on demand. Our club's
roof access port is only ten feet from the bigger dish ;-) It will cost
the school major $ to take this stuff down, so it would save $ to let us
use it - and might provide lots of useful hands-on microwave experience
for some of our future graduates. That's my argument, anyway ;-)

If anybody knows of some microwave homebrew resource and project pages,
let me know!

regards bobm
--
************************************************** *********************
* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
********************Standard Disclaimers Apply*************************