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One quick comment...it didn't take all that long to drop it down to under 16v...especially if you accidentally leave it on over night...

Thanks for checking those voltages. Yeah, I am not sure why my Vbe is so high. The resistors are of correct value R1=470 Ohm and R2=97K (I do not think +/- 3K would matter on 100K resistor) and placed correctly on the board. The transistor in the kit is C2570, placed correctly. No shorts, no opens. Oh well...

I worked AO-51 tonight with the preamp inline. This was a 41 degree pass for me. One thing I noticed this evening is that with the preamp on I started picking up the satellite almost immediately on the horizon. In the past, I was never able to do this...I didn't start picking it up until it had some elevation on my location. I switched the preamp off and on a few times to verify and was really pleased at the difference it made. I could hear it through it's entire pass.

I worked AO-51 tonight, too. Preamp kit is in the mail. Did you pick up your project box and 9V battery clips locally, or do you have a secret source

...Tom

I got the project box and battery clips at Fry's Electronics. The box had mounting posts (for screws) that were in all the wrong places, so i had to use a dremel tool to cut them out. I saw some project boxes at the electronics swap that would have worked better. The main board is just hot glued to the project box. I was a little hesitant about doing it this way, but it seems to be working out OK. At least that way if I have to pull it back out to replace something, it won't be too difficult to lift off the box. The battery clips are velcro'd to the board. I did it that way because the clips are REALLY strong and it can be tricky to get batteries in and out of in that small space. By making the battery leads a little longer and mounting them with velcro, I can lift them out and use two hands to do it. It seems to be working.

BTW, did I work you? I don't have a voice recorder so I'm not even trying to keep a log.

Negative. The passes I've been working lately have picked up So. Cal to Alaska. I need to work some lower angle passes to pick up more mid-west and east coast contacts. Farthest to date from western Washington has been Ohio for me.

I'd also like to get up on a hilltop and work a low pass to the west, and see if I can hear any Hawaii stations.

This is just a whole lot of fun with 5 watts

Tom / W3ROK

Tuning up this preamp could be easier if they included a variable capacitor for the RF input C2.
But for a $15 kit, i doubt that would be practical.

i'm not sure if they use the 2SC2498 or the 2SC2570A, but the latter would be better due to lower noise.

The best of the best preamps use the Agilent ATF10136 gas-fet or similar.
you could google for that and find all kinds of incredible LNA designs.

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