I had a few extra hours today...built the 1202 wattmeter, covering 2m and
HF-6m.
It's solid. It's black and about 25 ounces. The meter is nice and
readable (two watt scales, plus SWR). The kit contains four (yes, FOUR)
SO-239s, two LM-358s, a mess of pots, a few switches, and various other
caps and resistors. You have to wind a single toroid, which is actually
constructed (by you) of two different toroids to balance out the
performance. It will run on external 9-14 VDC or a 9V battery (cap
included!).
One switch (an SPDT center-off) was bad in one direction; I'll be calling
TT about a replacement when the group purchase is made.
On VHF, I couldn't get it to read anything for a couple of minutes; that
was on both scales, independent of SWR/Power, so I suspect THAT was the
other switch (there's a separate amplifier for each power scale/direction
combination). Then it suddenly started working, and has continued to do
so...hmmm...
Once calibrated to my HM-2140, it was rock solid - 10 watts on the 200 watt
scale = 10 watts on the 20 watt scale. I calibrated the VHF side with my
Alinco mobile rig (5/50 watts).
I have yet to try adjusting the HF low scale for 2 watts full scale, but
I've heard it can be done.
The 2m side uses a monimatch stripline (actually, a pair of them). There
are four germanium diodes used in the project, and if you can match two,
and use them for the VHF side, the accuracy will apparently be
considerably better than the worst-case spec (+/- 10% full scale).
The manual was flawless and very easy to follow, as with other T-kits.
When turned on, no signal present, it drew 900 MICROamps.
I plan to use this particular unit for 6m and 2m. With 6m E-skip season
coming (eventually) I think it will be nice to have...
The meter fits between the subassembly and the front panel, and I'm
investigating backlighting the meter with a couple of LEDs.
Unfortunately, this bumps it up to 15 mA :) so maybe I'll just leave it
alone.
Price - $49. With the group buy, it comes down to $44, no shipping chg.,
which is a STEAL for a meter that accurately measures from 160 - 2
meters, up to 200 watts.
DO NOT FORGET! I am the East Coast hub for the QRP-L TT group purchase.
* Scott Rosenfeld NF3I Burtonsville, MD FM19mc QRV 80-10/6/2/440 *
*** 6m 75 grids worked on 8 watts *** HF 138 cfmd * QRP-L #147 ***
** QRP ARCI #9054 ** DXCC/WAS/WAC *** 100% dipole powered HF/6m **
* 301-549-1022 h / 301-982-1015 w *** 145.490- 147.225+ PL 156.7 *
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