tuning at low power of course makes total sense, i ws just wondering why you have to do more tuning at higher power rather than tuning completely at low power. Does the tuning change a bit depending on drive power, or as the amplifier gets toasty warm?. It is sad that after being a ham since 91 I have never keyed a transmitter that output more than 100w.
On Jan 23, 2014, at 3:02 PM, Alan R. Downing <[log in to unmask]> wrote:
> You never want to tune an amp up for your ultimate desired output. It is
> generally best to bring your power up in 3 or 4 steps. For example, if I
> know that my ultimate drive power will be about 100 watts, I will first tune
> up at about 25 watts, then 50 watts, then 75 watts, and finally 100 watts.
> The steps aren't exactly critical, just as long as you bring your drive
> power up in 3 or 4 steps. Waiting 10 or 15 seconds between steps is also a
> good idea as you won't heat up the amp too quickly.
>
>
> HTH
>
> KD7GC
>
>
> Alan R. Downing
> Phoenix, AZ
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Michael Thurman
> Sent: Thursday, January 23, 2014 11:53 AM
> To: [log in to unmask]
> Subject: Re: W8JI's tuning suplement
>
> stupid question since i do not own an amp, but what is the purpose of =
> increasing power and then tuning more? is it to get a usable meter =
> reading? I was always under the impression that tuned was tuned no =
> matter the power because once tuned formeximum efficiency further =
> retuning shouldn't be necessary. Everyoen here having amplifiers makes =
> me think that if I win the lottery I might someday have one too
> On Jan 23, 2014, at 11:44 AM, Mike Ryan <[log in to unmask]> wrote:
>
>> Hi Steve:
>> =20
>> I've been reading through that info already including the tuning
>> supplement.
>> I think I'll use his A.M method but in CW mode. That is, preset the =
> knobs
>> to the initial start settings and band, set the exciters drive to 10 =
> or 20
>> watts, key down for no more than 5 2NDS, adjusting the plate for max =
> power
>> at that level, or pitch with the TW-1.
>> Go back to stand by, setting the exciter up to about 60 watts, =
> rekeying
>> increasing the load and tweaking the plate, then just switch to SSB,
>> reducing the drive to around 45W or so and just go ahead and operate.
>> I don't like is actual CW tuning method of pre-setting the exciters =
> drive
>> at 80W prior too keying down, adjusting the plate and load controls.
>> I'm no expert but that sounds like a good way to blow the crap our of
>> things pretty quickly. LOL
>> =20
>> 73:
>> Mike
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