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Reviews Categories | Ham radio kits | SDR-Kits PAOKLT Si570 Standalone Low Noise Synthesized VFO kit Help

Reviews Summary for SDR-Kits PAOKLT Si570 Standalone Low Noise Synthesized VFO kit
SDR-Kits PAOKLT Si570 Standalone Low Noise Synthesized VFO kit Reviews: 5 Average rating: 4.2/5 MSRP: $currently 47 to 98 £
Description: Frequency coverage is from 3.5 MHz
up to 1417 MHz, depending on the type/grade of Si570 device
fitted. The minimum tuning step is
selectable from 1 Hz, 10Hz, 100 Hz, 1kHz upwards.
Product is in production.
More info:
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You can write your own review of the SDR-Kits PAOKLT Si570 Standalone Low Noise Synthesized VFO kit.

KA9P Rating: 5/5 Sep 10, 2018 02:52 Send this review to a friend
Nice product, great support  Time owned: 0 to 3 months
Mine is running as advertised and Iím happy.
Iím posting this review primarily to say how pleased I am with Janís tech support. I had a problem on start up that I eventually traced back to a tiny filament of solderwick under the Si570. Jan provided great advice twice, with quick turnaround, that got the problem resolved quickly.
Iím buying another for the next receiver project.
G4AON Rating: 2/5 Jan 15, 2016 05:52 Send this review to a friend
Hopeless user manual  Time owned: 6 to 12 months
Given the lack of synthesizer kits, I suppose this one is "OK", but the manual is a hopeless muddle.

The latest manual on their web site, as at 15th Jan 2016 (manual v5.4), doesn't include the change to the band data outputs between firmware v4.19 and v4.20, all the bands have been moved up one! Anyone with an older kit, who uses a band decoder, would need to scrap the decoder when updating their firmware.

The synth firmware also doesn't include a proper "lock" feature, it does lock the tuning encoder, but in so doing it removes the IF offset. A huge oversight.

It would have been a good idea if the frequency was stored after being left on frequency for a minute or two, so it returns to the last used frequency on power up. Also, a variable tuning rate would be nice. Both these features are included in the obsolete Cumbria Designs synthesizer (which also uses an Si570 i/c)
YL3GND Rating: 5/5 Apr 11, 2015 11:20 Send this review to a friend
Best VFO kit so far.  Time owned: 6 to 12 months
I purchased the 160 MHz CMOS version of the kit. So far the best synthesizer VFO I have tried. It consumes only 80...85 miliAmps. You should note that Si570 is not a DDS unit - its a PLL. And it produces square wave, witch is best for some mixers, but not so much for an others. In comparison with DDS modules (like those based on AD9850 or even worse AD9834) there are (or almost) not any "birdies" or "spurs" in the output signal. Except for harmonics of course. Theoretically PLL should have more close band noise than DDS, but on my quick n' dirty test - I didn't notice any. Signal appears to be pretty clean.
G1HBE Rating: 4/5 Jul 24, 2013 03:40 Send this review to a friend
Good kit, room for improvement  Time owned: more than 12 months
I started off with the 160 MHz version of this si570-based VFO, and it worked great first time. Only the rather fiddly and frustrating muti-way ribbon cable let it down. Apart from that, I was so impressed I got the 'fast' version (900MHz) and again the only annoying part was the ribbon cable.
The cheap mechanical shaft encoder is a bit low-rent and it makes the VFO feel a bit 'ratty', but I've fitted an old (but very nice) 500 step optical encoder and now it feels like a million dollars!
KD7RDZI2 Rating: 5/5 Nov 18, 2010 17:08 Send this review to a friend
Gone north!  Time owned: 0 to 3 months
This is the most advanced VFO. My unit goes up to 945Mhz, but a new Si570 has been recently released which goes beyond 1400Mhz. The last chip should also have a higher output in dbm.

The kit seems very easy to assemble. It was not for me!!! The optional case is pushed to the limits, it's very small indeed. It fits but I would have liked that the optional Tin plated enclosure a bit higher.

The optional coilcraft is difficult to install. The Si570 is not problematic at all. There are a lot of warnings about statics. I discharged myself several times touching a ground post but I did not took any other precautions for it. I also used a small 12Vdc soldering iron which was not grounded and the chip was not damaged. Also, investigating a problem I decided to remove the Si570. I used a heat gun and in few seconds was off and after I soldered the same Si570 again. The Si570 is not that delicate.

I thought several times that my kit was gone south but with patience came back to north!

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