[Elecraft] 7610 / k3 ... amp comparisons

[Wes Stewart]

I wish I could understand all of this.

On 7/24/2018 6:58 AM, Arthur Nienhouse wrote:
> */I will agree with everything said pasted below but for one thing which is 
> Fan Noise I'm a rag chewer around 30 wpm QSK the fan will ratchet up to speed 
> 3 after a few minutes of keying so the fan noise is very a subjective opinion 
> not right not wrong just is, being fair in my assessment mine is built from a 
> kit when they first came out.
>
> By the way as an Icom owner of both the 7300 now parked unplugged and for sale 
> and the 7610 the cw qsk is better in the 7610 but the K3 is my choice for 
> split frequency DX QSK exchanges over both of the Icom radios the 7610 is a 
> big improvement how ever I find it clumsy to work Split listening up stuff 
> .... the Internal Keyer in the K3 is much better there is a better range of 
> adjustments available in the Elecraft internal keyer ....would I like to see 
> it like the Supper CMOS 3 keyer choices heck yes ....Icom gives you little 
> choice my fist after a lot of practicing and paying attention is better with 
> the Icom but not as good as the Elecraft Mode A Mode B is most important 
> choice but even more choices would be nice like the length of (each element) 
> not just the spacing between each element.
>
> One important discovery the 7610 muted VFO A from a S9 signal just up the band 
> on vfo B while chasing the Baker Is DX-Pedition it took me a while to (find) 
> out this is what was going on wanting to master the listening up pile up with 
> the 7610 and only one VFO knob  takes getting used to the cw monitor side tone 
> is 5 taps deep in the menu to change I can not hear it well enough even set at 
> 100% you have to turn down the RF gain making the guy on the island weaker 
> copy then turn up the AF gain making the side tone for my fist louder so I can 
> hear what I'm doing on the paddle, (self defeating) and *stupid* The cw side 
> tone is tied to the *flipping* AF gain not separate like in the K3..... 
> *stupid*. If you can't hear the island on one VFO because a big signal is a 
> couple cycles up push his button never listening to *hear the guy on the 
> island* who he is working or know if he is calling Mr button pusher that kind 
> of qrm is not necessary nor productive to the run rate. Mr button pusher was 
> not working QSK was he waiting for a computer to tell him the island is 
> calling?????
> You can't fix *STUPID*..............front end muting from a big signal near by 
> is a problem. Now change to head phones you ears get blown up by the side tone 
> level needing 5 taps deep in the menu then adjusting it even one more time 
> *stupid* at the very least this adjustment needs to be in the MULTI button 
> empty spot menu ...........like it is for SSB don't hold your breath waiting 
> to Icom to fix this over site.
> Both radios drive the KPA500 well the hook up is straight forward easy to do 
> QSK  relays perfect the best.
> Oh yea Icom needs a menu setting SPK+Phones, a rear plug for 3.5 Mic input and 
> 3.5 Elec-Key input.
>
>  Back to Baker Is DX I finally gave up switched to the K3 bam in the log 
> ...... You get what you pay for there is a lot to like with the 7610 a lot, 
> many features you don't get with the base set up in many other radios the 
> price is really good but if you want to race  Pro Stock it is not cheep 
> performance counts and cost....
>
> Not sorry.. never have been on my choice I have put a helper fan on top to 
> push air as soon as the amp comes on cooling it from before key down lower 
> start temp. My shack is hottest room in the house the station is in a corner
> the helper fan is a Noctua fan NF-a9x14pwm low profile. To be fair a TV is 
> always going two computers big monitor all making the room hotter. I get a 
> couple more minutes till the temp runs to 65c kicks speed 3 on which is my 
> time out timer to turn it over,  the equipment is also stacked to save space I 
> found that at full song speed 3 kicks in if I'm in the middle of some sentence 
> and keep going the fan will run at speed 3 then go back to speed 2 .....be 
> nice to set the on set of speed 3 a bit higher in the tempeture range. This 
> amp is well built really does the job I'm happy happy happy, and yes my Z 
> bracket has the correct length hold down screws it will click when cooling 
> down ( not always ) not real objectionable for me the fan noise more annoying. 
> The screws were re-tightened after a heat cycle one at a time like you do with 
> race engines.
>
> I also took the advice to run the amp to its limit not at 400w out it does 
> seem the final is most efficient and running a tad cooler and longer before 
> speed 3 which is annoying and to be avoided in my opinion.
> The helper fan starts things from a cooler lower temperature as well giving a 
> bit longer run time to speed
> speed 3 another thing that can be done which I did before the helper fan is 
> run speed 1 at turn on keeping the idle temp lower.
>
> The Quadra has been in stand by ever since the KPA500 made it debut plugged in 
> and doing its timed maintenance mode, running the relays and noisy fans. I 
> would switch between them, now its not even plugged in I do not see the need 
> for what I'm doing....say that to say this I just might get the new 1500 if I 
> can sell the Quadra ( new 1998) never an inrush current problem first run 
> second version was the best, the only problem replaced the 4 meter lights a 
> few years ago. Elecraft ATU is so good compared to the Quadra with  RF 
> sniffing power needed is a speck in the ocean compared to the 50 watts into a 
> perfect load Mr Quadra want's to see.
>
> Regards
> Art
> ka9zap
>
> /*After much investigation and consideration I elected to purchase the 
> KPA-500/F.   Since I have the K3S and now the KAT-500,  I've "trained" the 
> KAT-500 for the antennas and frequencies on each band.  With the VFO tracking, 
> I dial the frequency and everything follows.
>
> Specifically the KPA-500 I find to be very quiet, it delivers 500 watts + on 
> every band, 160 - 6M.  Drive power is about 25 watts on every band.  The fan 
> is quiet and is of no concern even at the highest speed.   It does step down 
> quickly as the amp cools. Normally the fan is off until the temperature 
> rises.   Using it on FT-8 at 500 watts out, it will increment to #2 on 
> occasion.    The input always appears as a 1:1 SWR to the transceiver.    The 
> high SWR circuit does protect the amp and is fast.  With my station 
> configuration I feel as though I have a 500 watt transceiver, automatically 
> selecting antennas and tuning as needed.   I touch nothing but the VFO knob or 
> enter the frequency for the next band. Everything switches silently and 
> automatically.
>
> I come from a line of tube amps in the 1000 to 1200 watt class. Fans run all 
> the time.  Power output varies with band as well as drive requirements.  Most 
> seem to be optimized for 20M.   My last tube amp was a AL-80B and it was one 
> of the smoothest tuning amps I've used. Power out always 1000 + watts.   But 
> it required tuning with each frequency and band change.
>
> The difference in power is 3 dB or only 1/2 S unit.    All works for me.  I 
> vote for the KPA-500.