Sunday, 2 June 2019

IC-9100 or the new fangled IC-9700?

Well,

I've been using a Icom IC-9100 as by base station 2M/70cm and 23cm rig for a number of years. The radio cost a small fortune but now, due to the release of the IC-9700, is worth about 3 bob and a conker.

My friend at LAMCO has lent me a IC-9700 (their shop demo model) to play with so I thought I would document my findings.

The IC-9700 is a modern rig, a "twin" if you like to the IC-7300 - the later has proved an extremely low cost SDR radio which has sold extremely well.


So here are the things I see as an advantage over the IC-9100:
  • Modern SDR architecture on 2M and 70cm
  • Accurate power out setting (on the IC-9100 you turn the knob and put it about where you want it - the IC-9700 has a %age power setting display)
  • Accurate CW pitch setting - as with the power out on the IC-9100 you have to turn the knob until it sounds about right. or alternatively you can use a CAT command but that's a bit bonkers too.
  • lower noise floor on 23cm - listening to the Martelsham beacon on 23cm I am sure the noise floor is lower on the 9700 than the 9100 - I may have just made that up though as I cant have them both running at the same time.
  • The SWR meter on the 9100 is a load of Dingo's Kidneys on the VHF/UHF/SHF bands, it seems to work on the 9700.
  • Accurate ALC - the AC meter on the 9100 on 23cm is inaccurate but the 9700 seems to work OK.
  • Bandscope/Waterfall - hadn't been invented when the 9100 was made.
And here are the things I already dislike:
  • It drifts! When you TX and the PA fan kicks in the TCXO clearly drifts - that's bad, and I mean that's really bad. I have measured 5-6Hz drift on 23cm.
  • There is no RCA PTT or ALC jacks on the back for linear amplifier interfacing - you have to use the 8 pin din ACC socket - which in itself is OK but I want to connect my MicroKeyer to that socket so I can have multiple CAT ports and other gubbins. Seems quite an oversight.


So, in conclusion the lack of RCA jacks is annoying; but the drift is unforgivable. I will need to make an adapter so I can connect both the MicroKeyer and the linear to the same socket at the same time - some diodes might be needed as the MicroKeyer will use the PTT (ACC pin 3) as an INPUT to the rig and my amplifier wants to use it as an OUTPUT from the rig. According to the manual it's both.

Just for the record, I'm planning to have a bonkers bash at EME on 23cm; I will be using the transverter from here to go from 28MHz IF to 144MHz, then have a remote 23cm transverter.

The TS-890 can do this:


and I've even installed a garden based enclosure thingy to house the 23cm transverter and VLNA remotely:


As ever, I don't really know what I am doing so we will see.

Been a bit of tropo on 2M today:


Local conditions.

2 comments:

  1. Did you use data on 23cm ? if so, How did you find drift in frequency on 23cms on the IC9100.? Im looking at buying one but fear it will be unusable.

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    1. No drift at all on the 9100 - AC scatter example here https://g0mgx.blogspot.com/2016/10/microwaves-now-thats-really-nuts.html

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