QRP Club

QRP Station => Other => Topic started by: G0BVZ on January 28, 2014, 10:18:35 UTC

Title: Xiegu Technology switched capacitor audio filter
Post by: G0BVZ on January 28, 2014, 10:18:35 UTC
Ed Griffin is the only distributor of this item I know of:

http://www.wouxun.us/item.php?item_id=305&category_id=47 (http://www.wouxun.us/item.php?item_id=305&category_id=47)

Confusingly, despite the URL name, Ed does not handle Wouxun radios as detailed at length here:
http://www.wouxun.us/Good-Bye-Wouxun/Good-Bye-Wouxun.html (http://www.wouxun.us/Good-Bye-Wouxun/Good-Bye-Wouxun.html)

I own one of these filters. It works satisfactorily, though some audio artefacts are audible when the filter is at its narrowest setting. Physically, the thing is very small indeed, attractive to those craving dinky kit.

One photograph on the web site indicates a power requirement of 11-14v.  The example I received has that crossed out and 9v written on the label. Ed Griffin explained to me that the people who made the filter put on 11-14v even though it was designed for different voltages, hence the manual alteration. The description now says "Power can be provided by a 9v battery (external) or 12v power supply via a standard 5.5 x 2.1 mm power jack (center pin positive)." Pretty obviously, in the light of what Mr Griffin wrote to me, 12v means 12v not 13.8 or 14v so using your station 13.8v power supply is out. You need either a clean 12v wall wart or a suitable 9v battery lead.

It occurs to me that a case a few centimetres longer would have made it possible to keep the battery internal, which would have been a tidier solution for /P types: not a deal breaker, more a missed opportunity.

Vic