Tuesday, 28 June 2016

Yet more IC7300

I have taken delivery of an Alpha Delta 4 way coax switch to direct the output from the 7300 to the 4/6m antenna, HF antenna, dummy load or to the Anglian 2m transverter.
I have opted for the simple approach go interfacing to the Anglian and Gemini 2 PA.
I use just a 20dB power attenuator after the switch into the Anglian. I have the 7300 28MHz band power set to 8W. The reasoning is that if I was to accidently forget to turn the 28MHz power down (it is set per band) then the max that would hit the Anglian would be 1W and transverters tend to be more tolerant of overlod due to the usual input attenuator before the mixer. The 20dB attenuator is a25W unit which will stand a degree of overload before burn out.
My tests using the spectrum analyser on max hold etc indicated no significant spiking of output power when set to low power. I have seen some reports of ALC overshoot on SSB and CW. I have not seen this.

I had an interesting problem when set up. The Gemini 2 would fail to SWR when driving bove 100W output. This was eventually traced to the bulkhead lightning arrester on the antenna feed starting to trigger at this

level. The arrester has been replaced by an N bulkhead adapter. All is well now.

This evening saw several new locators added to my 6m total in the NAC contest. Now to try and leave  the system as it is now instead of yet another rearrangement.........


1 comment:

  1. Used same approach here with 9dB attenuator and power at about 25 Watts which gives my the drive level for my ME2T transverter. I too have seen no overshoot problems.

    This is a temporary setup to try the IC-7300 on 144, I still prefer my KX3 plus PX3, perhaps due to familiarity, but also because it has a noise gate and CW in SSB facility.

    I will use the IC-7300 for 50/70 MHz and leave the transverter for 144 on the KX3 so that I can monitor 2 bands at once.