[Hallicrafters] FW: SR-400A power output

[Walt Cates]

From: cateswa at msn.com
To: ac1wye at gmail.com
Subject: RE: [Hallicrafters] SR-400A power output
Date: Tue, 9 Sep 2014 15:46:00 -0500




Sandy,
 
Low power in CW with reasonable power in SSB is a common problem in the entire SR series. If you get acceptable power in SSB there is most likely no fault in the rig. It just needs proper alignment of two key items. First the VFO shift (VFO correction adjustment) section 8-8-D in the manual. The CW mode uses USB functions and is the VFO correction is not adjusted properly you will not have enough drive. Second is alignment of L15 and L16. A good test of the L15 and L16 alignment is to tune the receiver up in USB mode with input from a signal generator. Then slowly tune across the signal and watch the s-meter. If the response has a secondary peak on either side of the peak then L15 and L16 need to be aligned. 

Best Regards, Walt Cates, WD0GOF
 
 A generous person will prosper; whoever refreshes others will be refreshed.
 
> Date: Tue, 9 Sep 2014 15:43:27 -0400
> From: ac1wye at gmail.com
> To: hallicrafters at mailman.qth.net
> Subject: [Hallicrafters] SR-400A power output
> 
> Hello, Friends,
> 
> I'm starting to think about realigning my SR-400A. Hears just fine, but the
> power out isn't where it should be. I have several pairs of 6KD6s I can use
> besides the pair in the rig.
> 
> First of all, the present PA tubes appear to be balanced OK. I can get them
> adjusted to within .425 and .427Vdc on J11 and J12 with the rig tuned for
> as near 300mA as I can achieve.
> 
> What is strange is that my max PO into my Waters metered DL is about 80W in
> CW mode. No way that's right. If I go to LSB for instance, and whistle, I
> can get easily 175W. This is using 7250kHz. Can't explain the big
> difference, except for a need for realignment of the driver stages? I
> haven't used the rig for about six months. And, over the past two days,
> I've been on several favorite nets with good signal reports. But the PO
> seems to be in the tank. Probably needs to have the neutralization checked
> as well?
> 
> ​73,​
> ​​
> 
> 
> ​Sandy AC1Y​
> 
> 
> Alexander N. Gerli, Sr.
> 548 Allred Mill Road
> Mount Airy, NC 27030-2202
> 
> Scotsmen walk about 900 miles each year.
> A Scotsman drinks around 45 gallons of Whisky a year.
> Scotsmen get about 20 Miles Per Gallon.
> ______________________________________________________________
> Hallicrafters mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hallicrafters
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Hallicrafters at mailman.qth.net
> 
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
> 
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html