Re: [Elecraft] KPA1500 Drive Power

ent: Tuesday, June 5, 2018 2:36:52 PM To: Elecraft Reflector Subject: [Elecraft] KPA1500 Drive Power Noone has responded to my previous inquiry about the KPA1500 power drop-off due to heat. I would like to know if the KPA1500 power output actually drops off due to heat build-up or because

Re: [Elecraft] KPA1500 Drive Power

Read that: I owned Kpa500... Have a great day, Bill J From: Bill Johnson Sent: Tuesday, June 5, 2018 11:24:08 PM To: Elecraft Reflector; Roy Morris, Jr. Subject: Re: [Elecraft] KPA1500 Drive Power Roy, I owned and will soon have Kpa1500. Yes power will drop if

Re: [Elecraft] KPA1500 Drive Power

Sent: Tuesday, June 5, 2018 2:36:52 PM To: Elecraft Reflector Subject: [Elecraft] KPA1500 Drive Power Noone has responded to my previous inquiry about the KPA1500 power drop-off due to heat. I would like to know if the KPA1500 power output actually drops off due to heat build-up or because the SWR

[Elecraft] KPA1500 Drive Power

Noone has responded to my previous inquiry about the KPA1500 power drop-off due to heat.  I would like to know if the KPA1500 power output actually drops off due to heat build-up or because the SWR display was erroneously showing a power drop before it was fixed.  Thanks,  Roy Morris W4WFB _

[Elecraft] KPA1500 Drive Power

Does the KPA1500 drive power output actually drop off due to heat build-up or because the SWR display was erroneous before it was fixed.  Thanks,  Roy Morris  W4WFB __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/e

Re: [Elecraft] KPA1500 Drive Power

Now I'm really confused.  I observed the power drop when operating several times, as described below. However, I just ran a test, both with an antenna and a dummy load, and saw only a very small change in output, perhaps 50 W, which is inconsequential.  I even tried simulating CW operating in Q

Re: [Elecraft] KPA1500 Drive Power

On 5/31/2018 1:14 PM, Michael Blake wrote: Are you sure that it is not the K3(s) itself that has unstable output power. I see this occur on my KPA500 and it is not getting hot. Me too. Jim K9YC __ Elecraft mailing list Home: http://

Re: [Elecraft] KPA1500 Drive Power

Absolutely. I have never seen such fluctuations of either output or grid current with my other amplifiers. Scott K9MA -- Scott Ellington --- via iPad > On May 31, 2018, at 3:14 PM, Michael Blake wrote: > > Are you sure that it is not the K3(s) itself that has unstable output powe

Re: [Elecraft] KPA1500 Drive Power

Are you sure that it is not the K3(s) itself that has unstable output power. I see this occur on my KPA500 and it is not getting hot. Michael Blake k9...@mac.com > On May 31, 2018, at 4:09 PM, K9MA wrote: > > I agree with Rick: A way to slowly adjust the drive

Re: [Elecraft] KPA1500 Drive Power

I agree with Rick: A way to slowly adjust the drive power automatically to maintain constant peak output would solve the problem. I'd think the KPA1500 firmware could do this with the K3 via the accessory cable. Probably the K3 should revert to its original output when the KPA1500 is cold, or p

Re: [Elecraft] KPA1500 Drive Power

I've seen some gain drift with temperature, too. I've wondered if there might be a way to feed back drive power change requests to a K3, or other radio with adequate command capabilities, to maintain a target output power (say, 1500w) as the amp warms and cools. This should be done slowly - on the

[Elecraft] KPA1500 Drive Power

My KPA500 also has slightly inconsistent output. If I recall output drops a little after the first few seconds of key down. Perhaps it is normal for solid state amps as I have never noticed this with a tube amp. This may be more of a concern with a legal limit amp if you want to keep it as close to

Re: [Elecraft] KPA1500 Drive Power

: Thursday, May 31, 2018 9:42 AM To: Paul Baldock Cc: Elecraft Reflector Subject: Re: [Elecraft] KPA1500 Drive Power Yes, turning the drive up a bit restores the output to 1500 W. I haven't recorded it, but drive seems fairly flat band to band. (The K3, of course, saves the drive levels for each

Re: [Elecraft] KPA1500 Drive Power

Yes, turning the drive up a bit restores the output to 1500 W. I haven't recorded it, but drive seems fairly flat band to band. (The K3, of course, saves the drive levels for each band.) 73, Scott K9MA -- Scott Ellington --- via iPad > On May 31, 2018, at 10:16 AM, Paul Baldock wr

Re: [Elecraft] KPA1500 Drive Power

Yes, it does sound like a solid-state thing. Not enough negative feedback? It may be a reason NOT to run the fans continuously: Once it reaches 60 C, the fan control keeps the temperature fairly stable. 73, Scott K9MA -- Scott Ellington --- via iPad > On May 31, 2018, at 10:10 A

Re: [Elecraft] KPA1500 Drive Power

Can you safely increase the drive to get it back to 1500W? Another question: Is the drive requirement (amp gain) pretty flat from band to band? - Paul KW7Y At 08:10 AM 5/31/2018, Bill Stravinsky via Elecraft wrote: Yup, as the temp climbs the output drops some. Even though I'm glad I got

Re: [Elecraft] KPA1500 Drive Power

Yup, as the temp climbs the output drops some.  Even though I'm glad I got the solid state amp I still prefer tubes, hi.  The drop is anywhere between 100 to maybe 300 watts.I never really noted the exact numbers. BillK3WJV p.s. I'm thinking its a normal solid state thing. On Wednesday, May

[Elecraft] KPA1500 Drive Power

I'm using the K3 with the Elecraft interface cable.  I've noticed the the CW drive power required by mine varies considerably, both with temperature and SWR.  If I set the K3 output for a KPA1500 output of 1500 W output initially, the output will drop to perhaps 1100 W when the temperature stab