[AMRadio] AM Radio

[Bernie Doran]

Hi John: the DX 60 is rated at 90 watts peak. it is an efficiency modulation 
scheme using controlled carrier for AM as you know.    Even on CW a single 
6146 should not produce more that about 70 watts out.  In the controlled 
carrier mode the output will be much less and about the same as would be 
expected for use as a linear, probably in the range of only 10 to 15 watts 
and PEP as indicated by the factory rated of  90 watts.

The heath amp you are talking about uses 572Bs, not the Henry with 3-500s as 
you first mentioned.   However either one should have a gain of about   14DB 
or so.  That would be about 300 watts for 3-500s  when driven by 15 watts. 
So of course that makes a difference. The 572Bs are not capable of that but 
3-500s are. Neither however could be driven with 400 watts PEP.    That is 
the biggest problem with the original query about driving a linear with the 
DX100, far to much output and major changes required to the DX100 or 
swamping about 3/4  of the output power.

----- Original Message ----- 
From: "John Tate" <johndtate at post.com>
To: "Discussion of AM Radio in the Amateur Service" 
<amradio at mailman.qth.net>
Sent: Thursday, January 26, 2012 4:50 AM
Subject: Re: [AMRadio] AM Radio


>A couple of years ago, I would get on the air with my modified DX-60 
>driving my SB-200 and attempt to QSO from Louisiana to NJ with WA3JBT and 
>others. The "others" were much closer than Frank in NJ and I could usually 
>do okay with them but with Frank, his reception of me was very very hit and 
>miss, always at the edge of the noise level and some mornings were better 
>than others but rarely could we carry on a good QSO. It was extremely 
>frustrating to have one station in the regular group not able to copy me. 
>This was 100 watts and I always loaded my DX-60 heavy so the "controlled 
>carrier" aspect was rarely seen, in fact my 100 watt carrier would produce 
>just a tad over 400 watts PEP.
>
> Enter the Henry 2K4 amplifier with a pair of 3-500Z's. When I put the 
> exact same station except now the carrier was 300 watts and the peaks were 
> a tad over 1200 watts... I became armchair copy to Frank and the others 
> also replied with "wow" much better!! Yes I did switch between the two and 
> it was like night and day to everyone out there on 3.885 AM during 
> springtime early mornings.
>
> Now I had become a welcome member of the roundtable because everyone could 
> copy me without straining. It was a big difference and I felt comfortable 
> now in the roundtable. So yes, there you go, same antenna (inv vee) same 
> modulation level, same time, same freq response, same microphone same 
> everything but the power level and much better results.
>
>
> Now that is not to say that the 100 watts didn't get me into plenty of 
> roundtables without any problem, but in this case where the farthest 
> regular station was really having problems with me, the difference really 
> was desirable.
>