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Reviews For: Kenwood SM-230 Station Monitor

Category: Tools & Test Equipment for the amateur radio work bench

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Review Summary For : Kenwood SM-230 Station Monitor
Reviews: 4MSRP: 1099.95
The Kenwood SM-230 Station Monitor is a multi-function monitor scope which functions as a band-scope, monitor and tone generator. It is the ideal product for supporting, monitoring and calibrating equipment in radio stations.
Bandscope ±25/100/250 kHz, 10 MHz Oscilloscope, Wideband Transmission Monitor, RTTY X-Y Tuning Meter
Built-in 1000/1575 Hz Two-Tone Generator.....
Matches many Kenwood Late model (1990 and Newer) Transceivers

Product is not in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
KB3TUO Rating: 2017-11-05
Great complement to the 950! Time Owned: 3 to 6 months.
Although somewhat antiquated, this monitor is still very useful.

A modern panadapter is undoubtedly cheaper, more precise, and probably can view more than 500 kHz of spectrum at a time. However, try using a panadapter as a RTTY tuning aid, a transmit monitor, a two-tone generator for SSB calibration, and a standalone oscilloscope. The SM-230 will beat it every time, and all without using a computer! In regards to oscilloscopes, there's still a place on the bench for the analog type even in today's world of low cost, high performance DSOs, and the SM-230 fits the bill, even at only 10 MHz of bandwith.

Using the IF OUT 1 jack of the TS-950 (or any radio that has an IF out), the 8.83 MHz IF can be sent to the monitor so you can use it as a bandscope. Although this is the primary use, you can also hook the IF OUT 2 (100 kHz) into the oscilloscope input to monitor the received audio and even see CW waveforms to look for things like key clicks and chirps!

The CRT is pleasing to look at, and if you're familiar with oscilloscopes, setting the monitor up is easy to do. There is some warm up time associated with the bandscope function. That is to say that the signal you're listening to may not be directly centered in the display when you first turn it on, but a small adjustment of the horizontal positioning knob can move the signals around wherever you need them as the monitor warms up.

Overall, I've found that a great deal can be learned by be able to visualize the signals that one is hearing. The multi-function capability of the SM-230, combined with its ability to perform all of its functions well is why it gets a 5 from me. Not to mention that it looks great next to the TS-950! If you can find one of these for a few hundred dollars, I'd say go for it! I probably spent a little more on mine than I should have, but it's in mint condition and makes me smile every time the green traces start dancing around.
K7NG Rating: 2011-08-18
Useful station accessory Time Owned: more than 12 months.
Once upon a time this unit would probably have rated a '5' for its usefulness in a Kenwood station where the radio(s) have 8.83 panadaptor IF output. Well, it is still just about as useful for some functions but technology has passed the panadaptor part by. I now have an LP-PAN (a GREAT product) and PowerSDR-IF doing panoramic display work and other things. The SM-230 is still great for looking at the TX RF envelope, for looking at the RX signals via the 100 KHz IF of the TS-940/950, and for generating 2-tone AF for TX testing. I simply don't have any use for the panoramic display any longer. It looks nice next to the TS-950. As some of their functionality is obsolete now, the asking prices you may find are somewhat exorbitant, and unless you MUST have one for your setup you might want to pass.
WA1RKT Rating: 2011-02-26
Does not do trapezoid patterns Time Owned: 3 to 6 months.
Took me almost two years to find one of these at a remotely reasonable price (under $600 including shipping). Finally found one (NOT on ebay... if I recall correctly it was a ad). It works OK with my TS-940 and later with my TS-950SDX and TL-922A linear except for one thing...

One would expect that when a product comes out that supersedes another product, like the SM-230 did with the SM-220, that it would essentially do what the earlier product did but do it better and/or have more features. I regularly used my SM-220 in trapezoidal mode to monitor the linearity of my TL-922A amplifier. So when I finally found and bought my SM-230, to my dismay I discovered that it does not even have that feature. You can't do trapezoidal patterns at all.

I thought I did all the research I needed to do before buying this but obviously I missed that one, and that is my fault. Still, I stand by my rating. For the price these things fetch on the used market, it is just "OK", not "great".

One other thing, and this is absolutely NOT the fault of the SM-230 in any way and did not contribute to my rating, just something to keep in mind if you're in the market for one of these or ANY bandscope... if you have something like, for example, a TS-950 with a roofing filter ahead of the first IF, don't expect to be able to use the SM-230 in band-scope mode. It won't work. The roofing filter removes all of the signals out of the filter bandwidth and your bandscope will not see them. Inrad (the maker of the roofing filter) advises modifying the radio so that the bandscope picks off ahead of the filter.
KM6SD Rating: 2010-08-15
Kenwood's REAL Station Monitor ! Time Owned: more than 12 months.
This is a Modernized & Improved version of the old SM-220 workhorse, It is a far more stable unit with a 6" Braun style CRT, Looks awesome next to a 950/850/690 etc...Most of all, unlike it's forbearer; it is very stable in Bandscope mode, and the display is much easier on the eyes after hours of chasing DX and / or ragchewing......The only downside is the high price, but if one waits patiently, a good deal will come along...Try to get yours with all original manuals, cables & alignment tools. They come in handy & greatly add to the value. I even have the original double box and a NOS spare CRT...I use the RTTY function quite a bit for cross pattern as well as the monitor for TX...It has operated flawlessly for the past 15 years as part of my 950SDX/SM230/SP950/TL922/MC90 HF setup.....Analog still is the Best in my book.....