FW: FW: FW: Kit arrived...

[Brett gazdzinski-2]

 
Don,
Ok, but why always on the low side and not the hi side
of error?

2 to 3 watts out of 10 is 20% which is not that good,
and why only at the higher frequencies?
On 10 meters, it might say 12 watts out but only give 8
actual watts....
I want to know why it rolls off at the higher frequencies,
that is, the built in meter reads higher than actual power.

I suppose I should also test the rig at 14 volts, just to see
what the power out is.
The manual states that all the measurements were done at 14 volts
and I have been doing them at 13.8 key up.
My supply is regulated, but not that regulated..

And I wonder what sets the efficiency, output power VS current
and voltage in. Would that mostly be T3?

Eventually I might want to tweak that!

You can likely tell I like playing with radios more than
actually operating them, that is why the shack is almost
all home brew....

Well, maybe tonight I will do the spectrogram stuff!


Brett
N2DTS

>
> You may find some frequency dependency between 1N5711 diodes (I have
> occasionally noticed that), but I do not consider it a
> problem because
> the power indication and control point are not more than a
> few tenths of
> a watt off at any point if all is normal.  Considering that most
> wattmeter specs are in the range of 5% to 20% OF THE FULL
> SCALE READING,
> the diode detector in the K2 is actually more accurate than
> most if the
>   load is 50 ohms resistive at the frequency of operation (measuring
> with an ohmmeter is not suficient, resistance at DC is not
> likely to be
> equal to the resistance at RF).
>
> On your wattmeter accuracy, consider that even 5% of the 20
> watt scale
> can result in an error of 1 watt at any power level - and
> even the Bird
> wattmeter is only that good immediately after calibration - you must
> expect such errors in your measuring equipment (check the
> spec sheet and
>   verify the measurement by independent means if you really want
> accuracy).  The Diode Detector is actually more accurate than most
> wattmeters, but it must be used with a known good non-reactive load.
>
>
> 73,
> Don W3FPR
>

... [show rest of quote]

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com