[Lowfer] SAQ in EN90xn

[Michael Sapp]

Garry & All:   Perhaps a similar experience to what Garry was seeing.  I 
used my FT-847 for its 25Hz DSP filter but not having TCXO stability and was 
seeing

traces of a signal between the power line harmonics.  Whatever the signal 
was it did show up about 3Hz down from my center BFO frequency of 650 Hz, 
which is

consistent with the correction I have to make for ARGO calibration....

Possible startup test before 0800 message....

https://www.dropbox.com/s/ba6evtus2h19j2u/saq1.jpg?dl=0

Signal fragments in and out of noise just after 0800 UTC

https://www.dropbox.com/s/6drlczvrfnkepdm/saq2.jpg?dl=0

https://www.dropbox.com/s/c2fkk98iuu3wf5w/saq3.jpg?dl=0


I tested the binocular core antenna transformer that I have been receiving 
DK7FC on 136.172 for the past 2 years (as well sa SAQ attempts)  for 
insertion loss at VLF with the 600 ohm input of the HP3865c.

Numbers were -6.34 dB at 8.8kHz, -5.5 at 10kHz, -2.9 at 17.2 kHz, -1.79 dB 
at 25kHz and -1.03 dB at 40kHz.  Actual insertion loss likely a bit lower 
with the transformer being a 10.56:1 ratio from 75 ohms.... (~ 800 ohms) 
versus the 600 ohm balance input on the SLM.   The new 10.56:1 bino 
transformer (39T/12T)  based on (8)  F82-75 toriods used for the SAQ rx test 
showed about .16dB insertion loss at 17.2 kHz and .24dB insertion loss at 
8.8 kHz....

https://www.dropbox.com/s/c77j8qkwrt93vip/IMG_4162.JPG?dl=0


On air evening and overnite tests with the new antenna rx transformer, the 
results appear to perform similarly to the prior transformer from 100kHz to 
500kHz range as far as hearing all the common signals go. Background noise 
and atmospherics are noticeably stronger by ear and S meter  in the 8 to 20 
kHz range....

Thanks for the bandwidth and happy holidays to everyone.  73 Mike wa3tts





----- Original Message ----- 
From: "Garry" <k3siw at sbcglobal.net>
To: "lowfer list" <lowfer at mailman.qth.net>
Sent: Wednesday, December 24, 2014 3:43 AM
Subject: Re: [Lowfer] SAQ


> Jay, your grabber wide view looks like about what I was seeing, except I
> have a terrible 60 Hz picket fence at VLF. No problem for SAQ as it was
> generally in the clear, despite all its drift. Best I could do was
> occasionally catch weak traces on a spectrum laboratory waterfall set
> for about QRSS3 bandwidth. Was nice to have Laurence's grabber to see
> when and what SAQ was sending.
> -- 
> Garry, K3SIW, EN52ta, Elgin, IL
>


--------------------------------------------------------------------------------


> ______________________________________________________________
> Lowfer mailing list
> Home: http://mailman.qth.net/mailman/listinfo/lowfer
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Lowfer at mailman.qth.net
> Post must be less than 50KB total for message plus attachment!
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>