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Reviews For: Diamond SX-100 Pwr/SWR Meter

Category: SWR & Wattmeters & Dummy Loads

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Review Summary For : Diamond SX-100 Pwr/SWR Meter
Reviews: 11MSRP: 144.95
1.6-60 MHz, 3KW/300/30 Watt settings.
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
W6ACT Rating: 2019-11-01
Don't waste your money Time Owned: more than 12 months.
Just not a good meter what so ever. SO-239's are just garbage, meter is not accurate. Peak reading is a joke. No more diamonds for me.
UA1AFT Rating: 2014-12-26
Essential disadvantage Time Owned: more than 12 months.
SX-100 was recommended me as a good professional meter. Reality turned out worse. The device never got power higher than 400W passed through (at 3000W guaranteed), however, I managed to burn SWX-100 with WARC antenna (SWR~3,5). After disassembling the meter, I found both TX and ANT HF connectors attached to the measuring head's PCB through the holes of the same diameter as the diameter of SO-239's threaded center connectors. So, the gap between center connector and the ground was much less than 1mm that finally provoked HF sparkings and burning of PCB's glass fiber around the hole of ANT connector. Why manufacturer did not provide isolating sleeves around center connectors?
Additionally, backlight bulb of indicator does not stand 13,5V DC that is quite normal to power any transceiver for a long time.
K9ZF Rating: 2014-04-04
Good, but not great Time Owned: more than 12 months.
I think a 3.0 rating for this meter is a bit low. I've owned one for ~10 years. It works fine, but has a few issues.

Accuracy? Mine isn't terrible. I would say it stays within 10% and this is close enough for what I do.

The connectors on the back are terrible. Replace them. Don't use this meter until the connectors have been changed, or you are likely to let the smoke out of something. The connectors are the panel mount SO239's with the threaded center conductor. This is important because you need the threads and nuts to make the mechanical connection. If not for this flaw, I would have been OK with a 5 rating, but this is an obvious design flaw.

Panel light? Yeah well... Mine blew almost immediately. I never bothered to replace it...


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VK5AGC Rating: 2013-05-09
summary Time Owned: more than 12 months.
I can only classify this intrument as a 'kiddie toy'...I never take it seriouly.Setting it up is a nightmare, only the producer would perhaps be able to do this.No proper handy solid meters have been made in OZ for yonks, which is sad, so we put up with US rubbish...Buy one at you peril.
ZL1PO Rating: 2012-12-26
Awesome Part2 Time Owned: more than 12 months.
Update on my previous post back in 2004 under my old ZL1UST call.

Having had this meter for well over 18 years I can now say it is not so awesome anymore.
The dial lamp flickers and or goes dim and or want work.As mentioned by others and in my first post the SO239 sockets are an utter abomination.
With an indicated high SWR I assumed the coaxial feed line and or antenna were at fault.After inspection of the antenna and replacing the coaxial cable I then realized the SO239 fault had returned to haunt me :-(

I do not and would not recommend this meter.

Have a Happy 2013 New Year!

73 de ZL1PO
KB0GU Rating: 2010-03-01
Looks good but falls short. Time Owned: more than 12 months.
I rate this meter as only OK, for the aforementioned reasons on connector issues, the necessity to fully understand what the peak reading really means, and my own added beef; faulty panel lamps. After replacing the lamps twice, I swapped out the filament bulbs for white LED's. Now I do not think I will have to replace them again. Poor accuracy has already been addressed. The unit is compact, looks nice on the desk and serves its intended purpose here. Especially after having burned out, via overheated pick up torroids in a pair of identical Yasue meters that cost more. Now on to a Vectronics PM30 review.
M3JPE Rating: 2005-07-06
Excellent Time Owned: 0 to 3 months.
The Diamond SX-100 SWR & Power Meter is an excellent meter with all the functions needed for day to day use on a fixed station.

Not recommended for continuous swapping in and out of stations as the centre connectors are easily bent and there are limitations on ABSOLUTE accuracy, but 99.9% of the time this is not an issue.

Note: This meter measures from 3W (not 20W as stated in some places).
AI8H Rating: 2005-07-02
OK - But be Careful Time Owned: N.A.
The sockets on the back are goofy: as another reviewer noted, they need attention if even rarely excercised. There is absolutely no tensioning surrounding the center pins of the connectors. Mine was remedied by placing a small, circular 'keeper' spring around each center pin supported by a crafted piece of Teflon over the center of each below the springs.

The PEP readings are off a good bit (approximately 25 percent on the low side) and not easily adjustable. The SWR adjustment is very limited in range - mine is close, but not 'spot on" and also low.

Get one for about $40 in used, working condition in good cosmetic shape and it is well worth it.

This is a "Secondary" meter at best, but useful.

NL7ZM Rating: 2005-07-02
Peak Reading Time Owned: 0 to 3 months.
The front page of the instructions states.
The peak reading only indicates 70% to 90% of the actual peak value. I find this to be unacceptable.
I returned it for refund, the dealer did not question my reasons. This is something you don't find out until you buy. To the credit of the manufacture they admit the instrument is not accurate.
N4DEK Rating: 2004-12-26
Great Meter Time Owned: more than 12 months.
Been using these meters for quite some time and they have always served me well. Very nice meter that works great.