Usage comments: Have had this radio on the bench now for 3 days. Very stable. RX seems same as previous models but seems to handle the FM interference better. Maybe we have not had the bad stuff from Russia yet! The VFO /channel selector is pretty stiff compared to my MK2 which spun pretty easy. In fact I started using the up downs on the mic to save my delicate fingers!! Icom mic sounds more natuaral to some but most give a big thumbs up to the original mic. Lots of depth. Other than that it just keeps ticking along as it should.
We have been examining the MK3 Optima for a week now and were not happy with theway the mic sounded on SSB so requested a change and now it is sounding the way we like so it is ready to go. While originally the MK3 was supposed to be a new board with all the recent improvements to the circuit built in alas it is not the case! The board is still the same as the last two productions but there has been an update in the software to improve stabilty on SSB.
Quote “PLL SYSTEM: MAJOR NEW CHANGES, IN-ORDER TO OPTIMIZE A STABILITY PERFORMANCE OF SYNTHESIZER IC MB1502 WORKING FROM A LOWERST FREQ. RANGE, CAUSED SSB NOT IN PROPER WORKING OCCASSIONALLY, IT NEEDS TO CHANGE OSC FREQ TO 4 MHZ, AS TO KEEP A SIGNIFICANT DRIVING LEVEL, THUS, XTAL AND BUFFER MODULE HAS BEEN CHANGED IN THIS MK-3 VERSION.” there you have it.. from the horses mouth!
The mic circuit has been modded a little and the SSB sound is fine. Medium without too much low emphasis. Not too happy with the way the fan is attached. previously the fan was slightly recessed. Now it is tacked on the back..tackily at that. I much preferred the fan with the slight recess into the heatsinks as it looked ao much more professional. This is the quickest way to determine if you have a Mk3 or not. The other way is to look at the wording on the front panel.
If it says 10-12m AM/FM/SSB TRANSCEIVER you have the new MK3. Actually there is no functional difference between this and the previous model. Looks like the dual functioning knobs are a bit heavier duty and the yeticom Optima has a slightly different mic layout. Not sure if all the radios will be set up like ours but this was the one change we requested after testing the radio.
I will have more after I get my Mk3 out of customs and on to the bench where it will replace the version 2 with the func on the VFO I have been using for some time. I will be performing side by side tests to see if I can tell any changes in the way the radio performs. I think this could have been Optima ver 2.6 instead of Ver 3!