[Lowfer] SIW & EAR

[wa3tts at verizon.net]

Garry & J.B. : Atmosphere temps and sky noise lower this afternoon.  I had to run visual levels 35/35 on ARGO for EAR for QRSS30  and 47/47 for SIW on QRSS60 to limit blooming...
EAR best signal was -60 at one point and best avg background noise -81.8...Good >20 dB SNR at times
https://www.dropbox.com/s/u3ov2sznpjuydyr/earoct5.jpg?dl=0

On SIW I started later than usual as by 5pm local the path is usually fading away. But condx actually improved a bit with best SNR at -75 and average background noise best level was -83 at one point
https://www.dropbox.com/s/0crx0mrimr5ahpj/siwoct5.jpg?dl=0

So I would say 5 to 8 dB SNR over the capture interval.

I'm running a RC termination on the NW EWE built into the 75 ohm A/B switch in the field near the antenna transformer.  The RC components are 75 ohms R+ 22 ohms R +  .018uf  (closer to .0175uf actual) 630V chip cap.
Through the SE EWE 11.11:1 transformer (termination end of antenna)  that transforms to about 1077 R - 550 j ohms and makes for a deeper null on the EWE cardio pattern...
https://www.dropbox.com/s/2809yc8x0ew4r28/185ewe.jpg?dl=0

I'm seeing about 1.35:1 SWR at 185 kHz...lower than expected for not having a +550 j ohm inductor in the antenna system---so my guess is the 11.11:1  antenna transformers have enough excess "L" to get close to a match condition.

https://www.dropbox.com/s/3n8oo04j9yjxsd7/IMG_1446.JPG?dl=0   (NanoVNA through 9th order 300 kHz Butterworth LPF and 185 kHz bridge-T diplexer to antenna---to block strong local AM stns).

Hopwefully not TMI...tnx for the beaconing Gentlemen.
73 Mike wa3tts

Garry: 10GHz test in August was great from Perry Park, OH EN91kt.  I pretty much fiilled up a log page over several hours.  Good evap ducting for an hour or two as at one point you could pointa dish straight up and work the Canadian "Lake Runners."   Some rain scatter and tropo as well asboth WW8M and K2DH had good signals all day from the opposite ends of the lake...I stress overequipment performance all the time with a microwave outing. Usually the transverter goes on a WGload and directional coupler and spectrum analyser to verify TX power and do RX test with small signal beacon beforeheading out.  Way too much to organize for a (fun and restfull) weekend, but it usually turns out to be worth the effort... ~:)


-----Original Message-----
From: Garry <k3siw at sbcglobal.net>
To: lowfer <lowfer at mailman.qth.net>
Sent: Thu, Oct 3, 2019 8:02 pm
Subject: Re: [Lowfer] Lowfer SIW QRV

Mike, thanks very much for the report. Jay perhaps after we figure out 
what's causing the QRSS on 185.2993 kHz to occasionally drop out we'll 
try some EbNaut. It cooled down a lot here so temperature is not the 
culprit.

Mike, sorry I missed you during the August weekend of the 10 GHz & Above 
contest. I heard you (and many others) fine Saturday morning but it took 
some hours before it was clear my TX wasn't working right. Switched to 
the backup radio but too late to catch you. Got home and found a control 
wire on the TX/RX relay was dangling in the air! Glad the SSPA has a 
circulator on it, hi.

73, Garry, K3SIW, EN52ta, Elgin, IL