I have a Palstar ZM-30. I bought it to avoid the MFJ unit. It also got
a good writeup in QST. After a short period of use, it became
dysfunctional. Palstar repaired it promptly. Paul at Palstar told me I
had inadvertently zapped it with static charge picked up off an antenna,
and to ensure I grounded the antenna shield and core to ground, and to
the ZM-30 case before use. He enclosed a warning label that should have
been included in the original package. He also said he had jacked up the
values of some of the diodes involved on the circuit board.
Actually, when it failed, I was testing a piece of coax in the shop.
After that, I was VERY careful, and NEVER did any work without a very
careful grounding. But, it zapped again. Now, I was not a happy
camper. I returned it with a letter of discontent. It was repaired and
returned, but I had lost my whole good weather window to work my rooftop
antennas before winter set it. Now, I would have to wait until next summer.
There were other comments by other users on this subject buried in the
eHam reviews I decided to sell it on ebay.
But, as things happen, the Noon Time Net (7268.5) asked if I would serve
as fill-in Net Control for Clyde, AA7WC. Before I could tackle that, I
needed to be able to put out about a KW on 40m. I couldn't, because my
antenna tuner (an LDG AT-1000) was in the shop (another interesting
story) and my 40 m antennas needed a tuner.
So I hauled out a Hustler 4BTV from storage, clamped it to a pipe in the
lawn outside my shack, and tried to get it tuned up flat for 40m. I
used the ZM-30 to help. While measuring and trimming a couple of radial
wires, the ZM-30 zapped again. I finished tuning up the antenna my
old-fashioned way, using the SWR meter on my transceiver and a lot of
trips in and out. I DID get it flat, though, and got on the air.
As we speak, the ZM-30 is enroute back to Ohio for the third time. This
time, it DOES go on eBay. It may work great - but, that's only WHEN it
works! I've already started looking at 259B's and am on the verge of
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