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Old 8th Mar 2021, 7:55 pm   #88
Matt kd4pbs
Tetrode
 
Join Date: Mar 2021
Location: Raleigh, North Carolina, USA.
Posts: 62
Default Re: Spectrum Analyser TR4172

That's how I determined the terminators were ~2K as they are... checking the input SMA and the output at the inter-board connection wire.
This is indeed a 6GHz 8753D. She's an oldie but goodie. It was gifted to me by a very dear friend and fellow broadcast engineer. Shortly after, it developed the typical HP problem on these series of VNA; a dead YTO. Thankfully I was able to locate one on that auction site, so all said, I have ~$500 into it. I've got no excuse for not playing around on the 5.8GHz and below microwave bands I guess... especially since I have lots of surplus 7GHz stuff just laying around that can probably be coerced operate down there.
I can certainly make an SMA cal kit, but I have no way to measure the polynomial corrections for it, so it would be less than ideal. Then again, it's likely that it would be far more ideal than slapping these unknown N to SMA adaptors on the ends and working from there. Again, I've got no real excuse... especially since the cables I currently use are on the order of 8 meters a piece of RG-400. Not ideal for microwave use at all, and very much impractical for benchtop use. It is another one of those "round tuit" things I need to work on. I know; I'm a mess - I'm sure it explains some of those crappy readouts you see from that Matt guy

David, I was doing some light reading on your old co-worker Siegfried. Amazing guy, he was. Interestingly, there is a local (for me) connection to him. The company he and some other of those HP guys created back in the 90s is right down the road from where I work, about 8 miles, half-way to our transmitter site. Small world!
https://www.stereophile.com/interviews/503/index.html
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