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Reviews For: JOHNSON MATCHBOX "LITE" 300 WATT

Category: Antenna Tuners/Matching Networks

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Review Summary For : JOHNSON MATCHBOX "LITE" 300 WATT
Reviews: 29MSRP:
Description:
275 watt Plate Input Power rated, 80-10 Meter tuner
Product is not in production
More Info: http://members.aol.com/tcsopr/vkgmbx.htm
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00294.6
N1BEC Rating: 2002-07-31
Have 3 matchboxes, they work good but have their limitations. Time Owned: more than 12 months.
Hi Folks! I've been using Johnson Matchboxes for something like 15 years. I'm pretty happy with them. I currently own two of the little matchboxes and one Kilowatt Matchbox. I use the KW mb with the Johnson 500 and the BC-610. It worked killer on a G5RV fed with open wire line. I had no matching problems of any sorts. I did modify it (in a manner so it can easily be returned to stock condition) so that the tuner is out on RX. I had to use a bushing to keep a high impedance line off ground, and it was hilarious when the RF from the JV500 ignited the rubber grommet due to extreme HV. I currently feed a 600 foot loop with the same ladder line. Again, no matching problems of any sort.
The two little mb's are in the little station in the house: One is stock, and goes to the 32V3, and the other has been "modified" before I got it (read: butchered) to do away with the T/R circuitry, so it's permanently in line. This one goes to the Kenwood 520-S. I'm working towards switching them i line with the old SA-13/U knife switches. Both untis work fairly well. One MAJOR complaint is the stock units seem to develop high resistance contacts across the receive contacts on the relay. It's a HUGE pain in the butt, pulling all the screws out, and cleaning the contacts. Most of the units I've found have this problem.
I've only had one instance where the mb has not performed well. My backup antenna is a 40 M dipole, fed by open wire. It tuned OK on 40, not at all on 20, fair on 15, great on 10, and only the high end of 75. Of course, using a 40 M dipole on 20 M, changes the feedpoint impedance from low impedance to a range in the thousands of Ohms, way beyond the tuning range of even the mb. The solution was to use a 4:1 balun, it still worked great on 40, and now worked well on 20, 15, & 10. 80 M op presented a minor problem, a short antenna presenting a lower impedance. I simply turned the 4:1 balun around, and now dropped the impedance by a factor of 4, and the 40 M antenna worked GREAT on 80M!
I have seen mods for using the mb on 160M, but have not tried them (nor do I want to mess up a good unit!).
I give the units a hearty two thumbs up!
KA3POY Rating: 2002-04-05
limited tuning range, no huge improvement in signal Time Owned: 0 to 3 months.
I bought a Johnson matchbox because I run wire antennas (zepps, ocfd, doublets, etc) fed with ladder line, had read all the literature of the evils of unbalanced tuners, and I wanted to remove the balun from my system.

So, as a not very scientific experiment I used my Elecraft K2 to run comparisons (all hf cw) between the matchbox feeding ladderline, and the K2 with ATU feeding a 4:1 balun feeding ladder line. In both cases the initial feedline coming from the K2 was 1.5 foot of RG-58. The ladder line ran out through a foam insulator to the antenna hung in the back yard. Some of the comparisons were back to back during the same qso. The comparisons were conducted with a number of garden variety variations of multiband wire hf antennas fed with 450 ohm line.

My experience was that there was no repeatable difference in signal strength on any hf band between the matchbox and the (unbalanced) atu/balun combination. However, there was a humongous difference in the number of bands that could be matched: the K2 ATU matched everything without a hiccup, the Matchbox matched some but not others and some of the bad matches were weird - like couldn't match 7.030 mhz on a 40M OCFD. I never found a wire antenna that the matchbox would tune 40,30,20,17,15,12, and 10 meters on.

So,the matchbox was ok but nobody gave me the +10 db signal report (or + anything, really) and I really need the convenience of working all bands with one antenna. So, I sold the matchbox. Your mileage may vary.

KA3POY
N4EKV Rating: 2002-03-12
Works OK, not great Time Owned: 0 to 3 months.
Feeding a ladder fed 160m doublet the Matchbox was not able to tune certain bands, like 40m and 15m, and couldn't hit 1:1 on several others. Repeatability was decent, but it certainly varied with weather. Decent WARC coverage by using the adjascent "traditional" band setting, but no 160m coverage.

When I replaced it with a Ten-Tec 238 I was able to tune 1:1 everywhere.
VE6XX Rating: 2002-03-11
a superb Time Owned: more than 12 months.
Greetings: I own two "matchboxes" & consider them to be excellent units. I must say that I find the comments of the gentleman who claimed a +10dB increase in signal strength when a "T" match tuner was exchanged for a different tuner to be eye opening to say the least.
What he is saying is that using his "T' match, if he feeds the tuner with 100 watts input, then 90 watts is dissipated in the tuner! Ninety watts would certainly heat up a lot of components! I have used a large number of tuners , including "T" matches, & if 90 watts out of 100 are being converted to heat, then I submit his measuring technique is faulty, or there is a parasitic resonance in the tuner! He claims a 10dB increase in signal by changing tuners. If the tuner has an input of 100 watts & he loads the antenna, & then changes tuners & the signal increases 10dB, then that tells me there is a loss of ninety watts(roughly) in the tuner.
Hard to believe! Ah! but I digress. The Johnson was & is a standard tuner for balanced lines.
The problem is, that it is hard to find one today that has not been altered in some way, or worse, butchered. They are an excellent buy.
Cheers! Brian, VE6XX
KD5QPF Rating: 2002-03-10
Oldie but Goodie Time Owned: more than 12 months.
I have the Nye-Viking version of the Matchbox and I'm such a fan I just bought a second one.

It's a real shame no one manufacturers an inductively coupled ATU anymore. The design is just so much more efficient exhibiting very little loss compared to more 'contemporary' designs.

Personally, I like playing with knobs (no 'clickety clack' auto-tuners for me). The icing on the cake is settings are "instantly" repeatable. Once you find the right setting for a particular band/freq just jot it down. Next time you visit that spot just dial it in from your notes and its right there like it oughta be!

Also, I do like the solid black Nye version instead of the two tone 50's Buick look of the EF Johnson ;)
W1EMJ Rating: 2001-05-06
Great!!! Time Owned: more than 12 months.
Works perfectly with my Johnson Viking Valiant II
Great tuner with a great ham radio heritage.
PA1HR Rating: 2001-02-14
Even better after modification Time Owned: 6 to 12 months.
I bought my Johnson Matchbox half a year ago from a SWL in Germany. On the internet I found a great site from W4RNL about this matchbox. Look at www.cebik.com/link.html. I made a very useful modification. Just loose every connection with earth! There must be only one earthconnection left, and that is one side of the couplingcoil. You have to isolate the right capacitor too! I did this by making a new part of the case for the matcher. I replaced the original by plexiglass! So I can see all the very beautifil components the whole time, it's really a great view and it works excellent! My antenne is only a 2 x 9 meters sloping dipole which I use for 40 till 10 meters. Some time I hope to install another antenna, so I can use 80 meters too. And I hope to buy a Johnson 1 kiloWatt match some time, because I own a Heathkit SB-1000 and I want to use the tuner in combination with my linear. Just try the modification and you will be more enthousiast about this tuner. No more TVI/BCI and great results on HF! 73, Hans PA1HR.
KK9H Rating: 2000-06-08
A classic balanced line tuner Time Owned: more than 12 months.
Last year at the Dayton Hamvention I came across a Johnson Matchbox that was in excellent shape so I bought it. I have always wanted one to use when we go up north for our summer vacations. When setting up a temporary station, I feel the simpler it is, the better. After putting up an 80M dipole fed with ladder line and using the Johnson Matchbox for all band operation, I am happy to report that this combination worked beautifully. I was able to easily get a good match on all bands from 80 through 10 meters and I received excellent signal reports. The rig used was a Kenwood TS-830. The WARC bands worked fine too by setting the Matchbox's band switch to an adjacent band and just tuning for lowest SWR. While my Matchbox has an SWR meter built into it, one of the cross-needle type SWR meters makes the tuning process much easier and faster. If you are looking for an inexpensive, easy-to-install all band antenna, the open ladder fed dipole is pretty tough to beat and the Johnson Matchbox is a great way to feed it.
N8PKN Rating: 2000-03-18
FINE TUNER FOR BALANCED FEED Time Owned: unknown months.
I own a low power version of the venerable KW Matchbox, its easy to tune, matches my 80m loop on all bands 80-6m down to 1:1 swr. I get nice wide bandwith once tuned, and only need to touch up occasionally at extremes. It's built like a tank and should be able to hold up to much more than its rated power. (I do not own a linear amp). If you run balanced feed get one of these tuners, if you own one, keep it, you will miss it. One down side, it does not go to 160m.