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Reviews For: WA4MCM GM-102

Category: SWR & Wattmeters & Dummy Loads

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Review Summary For : WA4MCM GM-102
Reviews: 6MSRP: 250.00
Description:
Handles Full Legal Power Across the Full HF Spectrum Plus 6M– The GM-102 will measure from 1.8MHz to 54MHz. Top range is 2KW full scale. Graphical Touch Display – The meter uses a 3.5” TFT display with an integrated resistive touch panel. All user controls are accessed via the touch panel. Peak Hold Capability – The meter comes with a user-selectable peak hold function that will smooth out the wild fluctuations when using SSB or CW and display your true peak power output. User Selectable Meter Faces – The user has a choice of three different meter faces: Traditional Needle, Bar Graphs, and Full Screen Digital. The needle face can be changed from displaying the forward power to displaying reflected power. The bar graphs and full screen digital display both forward and reflected power on the same meter face. Three Independent Power Scales – The meter provides three power scales: 20 Watts full scale, 200 Watts full scale, and 2000 Watts full scale. The forward and reflected power scales can be selected independently of each other. Always On Digital Display – The forward and reflected power as well as the VSWR is constantly shown at the bottom of the meter’s display screen in large numerals for quick, easy viewing. Remote Sensor Unit – The actual sensor unit is remotely connected to the meter via an inexpensive stereo cable with 3.5mm plugs on each end. This allows for its placement in-line without the need to reroute your feedline to the meter’s operating location. Computer Interface – Comes equipped with a USB interface and companion Windows application for viewing the meter on your computer screen as well as remotely controlling all of the meter’s functions. The communications protocol is published so that the user can create their own application, or integrate the meter into other 3rd party solutions such as Node Red
Product is in production
More Info: https://wa4mcmkits.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
2565
NF6P Rating: 2025-01-08
Digital Accuracy that Won’t Break The Bank Time Owned: 0 to 3 months.
Don Friend, KA4MGM, has paid homage to the Heathkit HM-102 with this digital SWR/Power Meter. My shack needed a good-quality meter for an upcoming QRP project and regular operation from the RV. I had my eye on this kit before QST Magazine gave it a favorable review last year. I saw an ad in the QRZ.COM classifieds from a ham who purchased the kit but could not solder anymore due to medical issues. I got a deal, and over the holidays, it was delivered.

This kit is packaged exceptionally well. All the parts were on hand. Several circuit boards are in the kit, and SMD components are pre-installed. The build instructions are excellent, easy to follow, and detailed. I spent about 8 hours assembling, troubleshooting a few issues, and calibrating the meter before final cabinet assembly. Only one coil must be wound, and it was not difficult once you got into it. It was my first winding adventure in a kit. As it turns out, the enameled wire was a trouble spot, and it took a good sanding of the leads and heat from the iron to get it operational. The coil picks up the RF in the sensor box assembly.

The only other trouble spot was properly installing the TFT screen assembly. I must have had a short or pressure point because the first tests showed a dim screen and erratic operation. I removed the TFT assembly and carefully reinstalled it, which fixed whatever problem it had. A good head-worn and illuminated magnifier helped in assembly and troubleshooting. A good solder sucker fixed a few solder bridges on close space pads on the main circuit board.

The calibration is straightforward and super accurate on all bands tested. I love that this meter works on six meters. The Peak Hold function is adjustable. It just works for me. To avoid RF issues, I placed toroid chokes on the cables connected to the power, sensor, and USB jacks on the meter. The Windows Application provided is a great way to get remote access to the data from the meter.

The GM-102 is a good-looking, practical, and accurate shack accessory. The bonus is that you get to build it. Other digital SWR/Power meters on the market cost a fortune but do the same thing. Back in the day, the Heathkit HM-102 was often the first accessory a ham built and owned. We’ve come a long way in technology, and the GM-102 fits the bill.
K8ERS Rating: 2024-12-09
Great Watt meter Even better kit Time Owned: 6 to 12 months.
Ill start out by saying I like to build. This was a good kit well layed out easy to understand instructions. As other have said that its a great addition to the shack and has good calibration. Would recommend this to anyone looking for a digital watt meter. The only thing that I would want is for a VHF/UHF version.
KB8NEV Rating: 2024-03-25
Watt meter kit Time Owned: 0 to 3 months.
I was told about this kit by a friend of mine. I purchased it about two weeks ago and finished the assembly this past weekend.
Instructions are very detailed and well organized and the fit and finish are excellent.
Operation of the meter is very nice, I downloaded the PC interface software and it is very nice to have this on the monitor as well as the meter itself. WA4MCM is very helpful if you have problems or questions and even responded to an email after made a mistake on the analog to digital board even though he was away from his home. Shipped the part to me and I was up and building again within a couple days.
The meter is a very nice addition to the shack and seems to be highly accurate after proper calibration, I highly recommend this kit.
W5SU Rating: 2023-09-30
Quality product; SPECTACULAR kit/instrux Time Owned: 0 to 3 months.
I'm leaving out the specifications - they're listed by the other commenters.

I'd characterize this as a LP-100A for roughly half the price. It works well and the calibration procedure is very straightforward.

But what stands out most to me is the level of detail in the assembly instructions and how well they're presented. When you go into the first few pages, you're presented with high quality very clear close-up photographs of all the parts - - each and every resistor, diode, solid state device, connector, nut, bolt, screw...everything! There's no possibility of confusing any components. Everything is organized into little ziplock bags, containing parts grouped together for each phase of assembling them. Also, I found WA4MCM to be very approachable and immediately responsive to any questions. I've assembled many Heathkits, Ramsey kits, etc - - none even comes close to the ease of WA4MCM's step-by-step instructions.

If I had to look under every rock to find something that could be improved upon...the peak hold seems to decay a little too rapidly. Also the lowest scale of Reflected Power is 0-20 Watts. Since it takes 20W for full scale excursion of the needle (or bar, depending upon which display is selected) if you're running QRP with only a few Watts or else using very low power to adjust a coupler, the Reflected Power would have to be relatively high before there's much action in the needle or bar display. Nonetheless, the digital display still reads accurately. These are observations, not complaints and I'll bet they can be managed by software updates in the future.

I would not hesitate picking up one of these!

KO4USA Rating: 2023-09-06
Great Kit - Very nice Wattmeter Time Owned: 0 to 3 months.
I purchased the GM-102: Graphical HF SWR & Wattmeter Kit at the Shelby Hamfest. Don - WA4MCM, the designer, was enthusiastic and very proud of his products. Having put the kit together over the weekend, I can understand why he feels that way.

The documentation is extremely well written, and there are videos available online that complement the assembly and operation of the device.
If you enjoy building kits equal to the caliber of Heathkit, and would like a very nice SWR/Wattmeter - all for a reasonable price, this is the ticket!

From the product's webpage:(https://wa4mcmkits.com/)

Handles Full Legal Power Across the Full HF Spectrum Plus 6M– The GM-102 will measure from 1.8MHz to 54MHz. Top range is 2KW full scale.
Graphical Touch Display – The meter uses a 3.5” TFT display with an integrated resistive touch panel. All user controls are accessed via the touch panel.
Peak Hold Capability – The meter comes with a user-selectable peak hold function that will smooth out the wild fluctuations when using SSB or CW and display your true peak power output.
User Selectable Meter Faces – The user has a choice of three different meter faces: Traditional Needle, Bar Graphs, and Full Screen Digital. The needle face can be changed from displaying the forward power to displaying reflected power. The bar graphs and full screen digital display both forward and reflected power on the same meter face.
Three Independent Power Scales – The meter provides three power scales: 20 Watts full scale, 200 Watts full scale, and 2000 Watts full scale. The forward and reflected power scales can be selected independently of each other.
Always On Digital Display – The forward and reflected power as well as the VSWR is constantly shown at the bottom of the meter’s display screen in large numerals for quick, easy viewing.
Remote Sensor Unit – The actual sensor unit is remotely connected to the meter via an inexpensive stereo cable with 3.5mm plugs on each end. This allows for its placement in-line without the need to reroute your feedline to the meter’s operating location.
Computer Interface – Comes equipped with a USB interface and companion Windows application for viewing the meter on your computer screen as well as remotely controlling all of the meter’s functions. The communications protocol is published so that the user can create their own application, or integrate the meter into other 3rd party solutions such as Node Red.

I highly recommend this Kit.

AD3G Rating: 2023-08-11
EXCELLENT METER Time Owned: 0 to 3 months.
Kit assembly / calibration start to finish took me about 5 1/2 hours.
All the SMD & tiny parts soldered, kit only requires through hole components...good for my not so good eyes.
Assembly instructions excellent, very well thought out. Calibration instructions also very good & calibration easy to do.
My assembled meter is very accurate as compared to my Telepost LP-100A.
I would highly recommend as I am very pleased with mine.