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Reviews For: KW 109

Category: Antenna Tuners/Matching Networks

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Review Summary For : KW 109
Reviews: 5MSRP:
Description:
Balanced 80-10m tuner with Dummy load, SWR / Power meter,Antenna selector switch.1kw rated.
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0054.8
G4GZG Rating: 2020-10-25
My favourite tuner. Time Owned: more than 12 months.
I've had lots of different tuners over my 42 year ham life.These range from simple L, to various transmatch designs and the now ubiquitous T match. I've had my KW109 for years and used it for quite a few years with a open wire fed doublet. Moving to a new QTH two years ago got me experiementing a bit and I fell out of love with the SPC transmatch as it often provided ambigous results ( eg two settings of 1:1 with only one providing decent output.) Recently I retired the transmatch and resdiscovered the KW109. Internally the circuit is a Z match that has its origins in a no switching PA tank circuit articel by W1CJL in QST many many years ago.
There are other versions made by KW and others , such as the KW107 which lacks the SWR meter and dummy load. The KW109 has both of these and a 1KW ( input to the PA, not output) rating. It was made in the UK where we only have a 400W PEP limit so won't compete at 1500W output.
The Zmatch circuit is very easy to adjust and can tune up virtually anything, including my W3EDP zepp fed. They are quite rare but if you see one, buy it asd they are very versatile and with the dummy load and power meter also make a good bit of test kit.
MM1EWA Rating: 2015-12-08
Toptop! Time Owned: more than 12 months.
Some may say they look a bit bulky and retro looking, but boy does it do the job!

I have a couple of KW-107 tuners, a KW-105, and one of these KW-109s they all function about the same in-terms of matching ability (very well in most situations) the main difference between this and its lower number brothers is the higher power rating, at least as I understand it.

If I could own only one tuner, this would be it.

I'd not hesitate to recommend it.

Michael - MM1EWA
VA6DWH Rating: 2012-05-14
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: 2011-11-08
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: 2010-02-20
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 !!