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Reviews For: NingBo HF-UHF power/VSWR meter, model DF2477

Category: SWR & Wattmeters & Dummy Loads

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Review Summary For : NingBo HF-UHF power/VSWR meter, model DF2477
Reviews: 1MSRP: 100 approx (USD)
Measures forward power, reflected power (absolute) and VSWR (as ratio) with simple switchable PEP compensation circuit
Measures to 200w pulse, 100 watts CW, in three ranges: 5, 20 & 200 watts
Dual sensor (1.8 to 160 MHz, and 140 to 525 MHz)
SO239 for all RF sockets
backlight meter requires 13.8v DC input
measures 6 x 4 x 2.5 inches approx
Product is in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
VK7ZJA Rating: 2007-07-31
Looks great on paper, but poor quality, avoid! Time Owned: 0 to 3 months.
Looking very much like a Diamond SX600 or Avair Av600 (both of which seem to be getting good reviews here) I thought it reasonable to assume that this product, the DF2477 might well have come out of the same production line. Perhaps, perhaps not. But the quality just isn't there.
I also note this product is also marketed by Cellwave as a model KW525.

When I received my meter, the CAL pot was terribly noisy - I had to apply firm downward pressure on it to make it work properly. Upon opening up the device, I found the cause was two fold: there was too much shaft lubricant applied to the pot which had contaminated the carbon track inside, and the pot body was bent out of shape causing the wiper to not make good contact with the carbon track - this being due to incorrect PCB locating hole positions. Fairly easily fixed, but fiddly.
I also noted that, despite the "QC passed inspection" sticker inside, a screw was missing from the VHF/UHF sensor shield cover.

Checking the meter's basic accuracy disappoints too. For example, a Hewlett Packard high quality dummy load measures as VSWR of 1.5:1 on UHF. I know from my HP scalar network analyser this dummy load is not that bad! Power measurements were also all over the shop, again compared to some good HP gear as a baseline. If I had the inclination and some descriptions of the function of each, there's about 8 pots and a few trim caps inside where I could get the overall calibration of the device a lot closer, I'm sure.

So, with poor QC to begin with, and definitely needing help with it's basic accuracy / calibration, this meter struggles to make a "2" as supplied. If you have the equipment to calibrate it against a known baseline, then it could work as a cheap all-in-one field meter for you.

But if you need something that's reasonable from the word go, then look elsewhere.