I bought one of these 45HP's new from one of the famous venders for such items and am pleased with the TX/RX performance on AM. SSB of course is OK but not the strong point of this radio. SSB stability is always a big question and this radio is OK there too. It's no 2970N2 but its good enough to use after you've cranked the mic gain down and turned the RF power up. All this can be done from the front panel as I've done nothing to the radio inside except for the jumper swap. This radio did 80+ watts peak on AM right out of the box. SSB was about the same around 70 watts. Echo was badass and the modulator is, well LOUD! Never had a radio with all these options built in. Very well made and the layout is different then most others, but easy to see the adjustments if needed. After jumper mod. I spent the better part of 2 hours beating up this radio. Ch 19 to SSB freeband, then some 10 meter work and the RFX 75 was warm to the touch but not burning hot. All of this was done with the SSB power wide open and AM set to around 8-10 watt dead key and swinging to the 80 watt mark on the Bird. I couldn't break it!!
Now as for the operator that had the weird SSB t/r relay "sticking" I found this by accident too. It appears that the S45HP is kinda sensitive to antenna reactance. I ran mine through a tuner to a dipole I use and because I had to use a large amount to TX capacitance to get the match right it would cause the radio to hang in between TX/RX. I didn't notice any RF power being produce but it killed the recieve. I put the radio into my dummy load and it worked like a champ with no issue and full power out. Took my MFJ antenna analyzer to my tuner and saw that the SWR was low but the reactance was over 15. Adjusted the tuner until the reactance was around 5 but of course the SWR was about 1.8:1, but no more t/r relay hang up. With that high level of reactance the antenna system begins to have a capacitive effect. This is quick way to explain this issue. One way to fix this is simply a stronger so to speak relay. Pull back spring tension greater etc.
Anyway if your antenna is close to resonance than you should be OK.
All in all a good radio and one I would buy again.
Now as for the operator that had the weird SSB t/r relay "sticking" I found this by accident too. It appears that the S45HP is kinda sensitive to antenna reactance. I ran mine through a tuner to a dipole I use and because I had to use a large amount to TX capacitance to get the match right it would cause the radio to hang in between TX/RX. I didn't notice any RF power being produce but it killed the recieve. I put the radio into my dummy load and it worked like a champ with no issue and full power out. Took my MFJ antenna analyzer to my tuner and saw that the SWR was low but the reactance was over 15. Adjusted the tuner until the reactance was around 5 but of course the SWR was about 1.8:1, but no more t/r relay hang up. With that high level of reactance the antenna system begins to have a capacitive effect. This is quick way to explain this issue. One way to fix this is simply a stronger so to speak relay. Pull back spring tension greater etc.
Anyway if your antenna is close to resonance than you should be OK.
All in all a good radio and one I would buy again.
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