Hardrock SWR Issue

[Mike Saeger]

I'm having a problem on bands above 20 meters. For example on 10 meters whlle my analog Daiwa CN-620 meter says the output is 100W and 1.5:1 SWR, the Hardrock 500 display says 100W output and 5.1:1 SWR. If I drive the amp higher than 100W it clicks off.

I put the output through my old Heathkit SA-2060A antenna tuner so I could get the SWR closer to 1:1. Same issue, the amp believes the SWR is 5.1:1 and clicks off at 80W.

No problems on 20 meters down to 160m .

Any ideas?

N9MS

[jcve...@gmail.com]

Hi Mike,

If your amp does not have the ATU then the problem is most likely a bad cable either inside or outside the amp. Next on the list is T303 or T304 on the LPF board but I have never seen an issue with a directional coupler that was frequency dependent.

Also try removing the CN-620 and connect the SA-2060 directly to the Hardrock-500 using the same cable that went between the CN-620 and the SA-2060.

73,

Jim WA2EUJ

[Mike Saeger]

Unbelievable! It was an EXTERNAL cable issue. I replaced the cable and SWR issue is GONE! Full drive back on 10 meters!

I feel like an idiot!