I probably didn’t phase that right, this is how my equipment is set up.
Radio Ant 1 to LA-1K > LA-1K Ant 1 to HF-Auto > HF-Auto connected to 3 antennas?
My setup is how it is described in the Palstar manual:
“2) Connect PTT Cable (Customer Provided) from transceiver to the LA-1K PTT Connector.
This connection is required for the LA-1K and is located on the REAR PANEL of the amp.
3) Connect a PL-259 Patch cable (Customer provided) from your transceiver’s antenna output
connector to the LA-1K’s RF INPUT coax connector.
4) Connect antenna (OR HF Auto) to the LA-1K’s Antenna 1 jack. Resonant antennas may be fed
directly from the antenna outputs if desired.
If using the HF-Auto (or another tuner), connect a second PL-259 Patch cable from the LA-1K’s Antenna 1 jack, to the tuner’s RF Input. The output of the tuner used is then connected to your antenna. “
Craig
KA6RWL
You say the HF Auto in front of the LA-1K. I run my HF Auto after the LA-1K.
Sent with Smoke Signals from my camp fire. ?
On Sun, Nov 3, 2024, 5:27 PM Craig Williams KA6RWL via <ka6rwl=
[email protected]> wrote:
Frank,
My LA-1K has been in the shop 3 times for the same replacement of the Q1 LDMOS chip. I run a couple wire antennas up in some Doug fir trees. The 160m antenna is a full wave with a very low SWR. The other antenna is a 80m horizontal Delta Loop that has a HF-AUTO in front of the LA-1K. These antennas are up at about 80 feet. I have heard the arc off that chip operating SSB on the 160m at an input of 40w, the others were off the Loop once in FT8 outputting 200w and once on SSB with an input of 40w. These have occurred twice in 2-21 and once in 2024.?
This is what Mark (Palstar Tech) said the second time it happened.
"I just wanted to ask that if your amplifier faults for BYPASS SWR, ??make sure that your antenna system is in order, as certain types of faults can damage transistors very suddenly.
These would tend to be faults that happen only at peak power levels, such as a wire antenna arcing to a tree branch.? Or a lightning arrester used on a non-resonant antenna with tuner.
?
I did not find any cause for the failed transistor we replaced.? A couple associated parts were also replaced “just in case”.
?
It is very unusual to have a repeated failure of this part.”
The amp did not fault to Bypass SWR and all antennas were checked each time with no issues found. The arc occurred between the chip and the same solder spot each time. So sometimes this may happen at least it is a relatively light weight amp to ship to Ohio for repairs. Despite this experience I still love the amp and the Palstar crew was great to work with.
Craig
KA6RWL
