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My power output measurements with an HP8640B at +1dbm using an
Elecraft W1 power meter and DL1 dummy load directly on the output of the amplifier:

1.8 MHz            10 Watts
3.5 MHZ             8 Watts
7.0 MHz             6 Watts
10.1 MHz           4 Watts
14.0 MHz           4 Watts
18.068 MHz       4 Watts
21.0 MHz           4 Watts
24.890 MHz       1Watt
28.0 MHz          1 Watt

YMMV

Tom ak2b

ki4mmm wrote:

Question - Should the power-out be greater if fed with a SSB signal?

Hi Greg,

This site gives a decent explanation on measuring PEP and CW power.
http://www.kk5dr.com/PEPtest.htm
*note 5/6/11 this link is broken.
If the amplifier were driven with a cw signal to 10 watts power output without distortion, then that is pretty much the maximum power output of that amplifier. The same amp driven with an SSB signal will not exceed that power and in fact would be considerably less on average since you are talking about peaks and valleys of power following your patterns of speech. CW uses all the power available since you are talking about a contiuous wave.

Tom, ak2b

Thanks Tom, that site had just the info I needed!

Leonard, I am measuring power with my o-scope, and I just watched a whole suite of your videos this past weekend (to refresh my memory so that I could tweak an MKARS80 transceiver that I just completed).  As I and many others have said before..... Great Videos, Thanks!!

Greg
ki4mmm

KC7NOA wrote:

Is this still accurate for current listing??

The specs are here
These are my notes on the amplifier I built going back a few years.  At the time I was hoping others would post their results so I could make some comparisons. As my post says 'Your Mileage May Vary'

Tom, ak2b

KC7NOA wrote:

i have a question ... T3 construction seems very confusing Is it just the same as T1 ??

Yes. IF you look just below the schematic you will see that Diz has given the turns count (Pri::Sec) per transformer ( 6T::2T for T3 and 7T::5T for T1).
The instructions for T3:
"___T3: Wind 6 and 2 full turns of 30 GA wire through a BN-43-2402 small binocular..... " threw me off a little- only because it was a bit inconsistent with the first line of the T1 instruction which says:
____T1: Wind 5 full turns of 26 GA wire through a BN-61-202 dull gray binocular.....
Maybe that's what you are referring to as confusing?

Let us know how your 2N3866's turns out.

Tom, ak2b

Or probably will just omit R3 & R30 and D2 & D5....

I do have a BPF  (will) on J2 ... and is grounded through a tapped coil. Id like to use a switched 13.8V for bias, and looks like bias for Q4 & Q5, and a constant 13.8V for Q2 Q3 and T1 will be driving another stage. (4 X mrf454's)

Last edited by KC7NOA (2010-10-22 15:46:50)

Looks like i goofed on T3 .. kinda distorted on the base of Q4.

Think i found my real problem; Since i'm not using the 2sc5739's and used 2n3866's i had to mount them oddly. I goofed on the final stage and swapped base for emitter ... I hope i didn't destroy the 2n3866's. I will soon have some info on output on 10M. I do wish though that my VFO/mixer had more output - the 10M crystal is down alot compared to the 40M crystal .... oh well.

Has any tried the RD16HHF in the finals with a slight mod to the base/gate voltage?

KC7NOA wrote:

KC7NOA wrote:

Has any tried the RD16HHF in the finals with a slight mod to the base/gate voltage?

Or how about the IRF520/510 .... its basically pin compatible ... with the original finals and driver. I'm going to give this a try soon. Need a few more parts to modify the inputs .... hope I don't have to replace the output transformer ....

Mike KC7NOA

Okay I'v replaced the finals and the driver with 3 IRF520N's ... 10m is at 5w, 75 is doing 12w and fore some reason 20M is putting out 29W ...

Still not quite what im looking for,
Not even sure if I'd call this progress ...  still wondering about the output transformer ... need to build a couple of rf voltmeters to solder into the stages to make it easier see what's going on.

Would those help the 10M performance?