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Reviews Categories | Antenna Tuners | KW 109 Help


Reviews Summary for KW 109
KW 109 Reviews: 3 Average rating: 4.7/5 MSRP: $(missing—add MSRP)
Description: Balanced 80-10m tuner with Dummy load, SWR / Power meter,Antenna selector switch.1kw rated.
Product is in production.
More info: http://
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VA6DWH Rating: 5/5 May 14, 2012 04:29 Send this review to a friend
Reliable performer  Time owned: more than 12 months
Had this unit for 2 years now....no complaints....when I run the extra squirrels I needed a tuner to match with that can handle 1 KW..does it with out complaint...good size meter is a bonus....for us that are getting older and don't see well...Never seen another like it..a little fiddly at first to get a good match...not great for quick freq'y changes...but tough and it gets the job done....with the dummy load on board its a complete package....I added a meter light...Good stuff from days gone by...!
 
WN9V Rating: 4/5 Nov 8, 2011 07:45 Send this review to a friend
Link coupled Zmatch circuit. a winner.  Time owned: more than 12 months
Yes, they are rare, but worth reviewing.

It is certainly not a mainstream design like the Tee matcher: You won't find any baluns inside.
The circuit inside can be compared to the old Harvey-Wells tuner and the balanced tuner by Globe. This model was the top of the line manufactured by KW Electronics. Mine is labeled "DECCA" not "KW" It makes a handy package, having not just the matcher, and a SWR meter, but also a dummy load and switches to let the operator choose loads: balanced line for 40/80M, balanced line for 20 thru 10M, or coax feed for a beam. The Z-match circuit is not as efficient as an L matcher, but the Z does have the virtue of having only one non-ambiguous combination of knob settings that provides a 1:1 SWR.

The claimed power handling of one KW is from the days when power was discussed in terms of INPUT to the final, so limit your transmitter output to 200 Watts if you object to the smell of burning styrene.

Operation is fairly straightforward as with any Z match configuration, it is most easy with one hand on each of the tuning knobs. I usually adjust the tuner by switching in an MFJ SWR bridge that puts out a very weak carrier, allowing you to take your time tuning up without much worry about interfering with others on the band.

No, this tuner will not match all open wire feeder loads. My experience is that given a random doublet and a random length feeder, this tuner does a better than average job. As is explained in the review of the Johnson kiloWatt Matchbox, you can help the tuner accomplish a match by a well thought-out application of an RF transformer between the KW109 and the feeder.

About appearance: This tuner with its perforated gray steel cabinet would look very much at home in a lineup of Collins radio gear. I think it is the best looking tuner around.

Quality of construction is good but not excellent, that is, coil forms of ceramic would be preferred over the plastic forms in use.

Availability: If you really want a link coupled balanced matcher, the Johnson Matchbox is much easier to find. In 30 years of attending swap meets, I have never seen another KW109. Just mine, purchased from a Canadian ham. There are numerous articles on building a Z-match type antenna tuner and that may be the best route if you want something that approximates a KW109.

Thanks for reading this review of my favorite antenna coupler. I hope you saw some features here that you can employ in a nice homebrew version.
 
G0LJS Rating: 5/5 Feb 20, 2010 06:32 Send this review to a friend
A keeper  Time owned: 3 to 6 months
This a rare Item. I have only seen this one example. Construction solid 60's British. Will provide match in most situations. With built in Dummy load ,power meter ,swr meter a very flexible unit capable of handling 1 kw. A KEEPER !!
 


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