Re: ic9700?


Paul G4KZY
 

Hi Alwyn,

I'd like to keep this positive, so please don't take offence at what I say or think I'm trying to criticise.  I would like to hear people's views for a reasonable alternative to the 9700 in various applications.  Ben asked if the 9700 would make a good replacement for his FT-817 as a microwave transverter driver and lots of people said "No!" for various reasons, but few suggested a good alternative.  Whilst far from perfect, I think a 9700 would be an improvement over an 817 in nearly every aspect.  Maybe I’m wrong, in which case perhaps others can suggest a better option?

Your views (Alwyn) are rightly considered authoritative, which means people will listen much more to what you are saying than what the likes of me are saying.

It is interesting that you think the Rx performance of the 9700 is its greatest weakness, and if I remember rightly, you measured (or perhaps reviewed) the Tx performance of the 9700 a couple of years ago and mentioned that on 2m it (just about) meets the RSGB VHF contest transmit composite noise specs for small stations.  Most complaints on this thread are about the Tx performance – principally on 2m I think?


There are some whose definition of "serious contesting" involves 4 or more antennas and one or more kW amps.  Clearly a 9700 is not appropriate for driving that lot.  However, I think that many folks use a 9700 it for what they consider serious contesting, perhaps in the AR sections or low power sections of RSGB contests.  The 9700 is, IMHO, a good option for this, and they are used by a number of well-regarded contesters.  After all, for a 100W power output, the "serious" alternative might involve an HF rig, a transverter (hopefully not from Ukraine) and a linear amplifier (hopefully not an MML100).  The scope for "inexpert" operators getting a bad signal out of that combination is far greater than the scope for overdriving a 9700.  So, it would be good to hear about others suggestions for a simple mobile / portable setup for an AR contest entry which would be an improvement on the 9700.

Similarly, I'd be interested if you could elaborate on what you meant when you said "its greatest weakness is the poor A/D accuracy on receive which makes it not much use when a band is busy."  Apart from a high quality HF rig and transverter, is there a better alternative?  The main problems I had in last week's UKAC were related to the S9+10dB intermods from the next-door station and AFAIK the best receiver in the world can't do much about that.  Again, is it that you need to put 3 or 4 boxes together to get an improvement, and if you do that how much improvement can you expect?  In other words, how busy do the bands have to be and how useless does the 9700 become under those conditions?  In fairness, I think your talk last year was very illuminating on this particular topic.

Going back to Ben's question, what would anybody suggest to replace his FT-817 as a driver for microwave transverters with IFs of 144MHz and 432MHz, as is an improvement over a 9700?

 

In closing I want to observe that your talk at the Convention last year has been widely praised, and I for one found it both fascinating and educational.  It made me think of a number of different aspects of my station which I hadn’t thought of before and it serves me as a useful reference for performance benchmarks,  Thank you for your work, and let’s hope that the likes of ICOM and Yaesu are listening.

 

Best wishes,

 

Paul G4KZY

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