How to calibrate your Daiwa CN-901HP SWR / Wattmeter 

Thank you for the video and link - very useful! Best 73!

Handy, thanks. I've just bought one and hoping it arrives unwrecked and doesn't need recalibrating. If it just needs a tweak, it's handy to know the ins and outs.

JUST RECEIVED NEW CN-901 HP TODAY..THX FOR POSTING VIDEO AND SHARING YOUR KNOWLEDGE..BE SAFE AND STAY WELL EVERYONE.( DESPERADO 56 NORTH OF TAMPA FLORIDA ) 73's

Yes thank you for taking the time with this particular meter. Just purchased one. USA AL

I thought I had a problem with my FLEX 6400 in terms of RF output. In troubleshooting, I used a different MFJ meter and found that the problem was with the CN-901. This video allowed me to fix the problem. Thanks for taking the time. 73 KK2L

Good Show Mate I like your digital meter the best then the diamond Cheers & 73s

I have a Daiwa swr too, but the V series version, it's only capable of up to 200 watts, so the question is can it be made into 2 kilos, because if i look at the PCB, the paths for the calibration potential, and others are same like that a hp series...

Nice video, just to let you know the diamond was measuring reflected when you said it was 20w, as the switch was on "ref"

So what about the watt loss through the multi coaxial connections??? DA

Nice video. It all makes sense. I just received my CN-901HP. It hasn’t even been connected yet but shows an indication of 9W Fwd and 2.5W Rev. This is not an electrical calibration problem since the meter is not powered. An attempt at zeroing the meter using the zero set screws using a small jewelers screw driver makes absolutely no change to the meter movements. Is this device defective? I made a call to Daiwa’s US distributor support who tell me that there is nobody to take my call. The retailer does not answer their phone.

Good description but what is the purpose of VR1, VR2, and VR3 on the left side of the diagram. Are these used for calibration purposes and if so how are they to be adjusted?

Good video, I wish you would've explained a bit more how you actually calibrate the meter. Do you turn the knob you showed inside? Also, do you have to go through the 20W, 200W and 2kW knobs and adjust them all? What meter do you prefer, Daiwa analog or the digital MFJ you have there? Thanks!

How do you calibrate reflected power???

Mine arrived today and like yours it was all over the place. Both meter were not set at zero, the calibration was out on all three settings and the light switch on the back was broken. I fished all the bits out, re-built the switch and refitted it, calibrated it and all is working now. Would of been sending it back had it not been for your video, thanks. What are the 3 pots on the left of the circuit diagram doing?

hiya, I got one of these meters and its not that old and its just suddenly started to show a forward power reading of about DOUBLE of what it should be !!! so looked around for some info and found this.... ( according to my meter, my Kenwood TS50 is putting out 250 watts!!!-- anyways I notice on your meters a big difference in SWR from the Digital which shows 1.66 and the Daiwa shows 1.3 ??? that's a BIG difference ???many thanks anyways for the Video

I may have missed it but did you mention that you should adjust the needle on the front to the ZERO mark if it's not already there? I have discovered that many videos show the needle is either above or below the ZERO mark which is Not the proper position for an Accurate reading.

Useful stuff, mine is low by about 20%. Going to compare to a bird that another local ham has. If I can get within 5-10% ill be happy! How accurate would you say they should be? Say if I went for calibration on 40m, would 80/20 be pretty close still? How much of a difference do you think one should expect?

Calibration work on at both average and peak? How's the av/peak buttom supposed to be?

Thanks for the description... However, in my watt meter same model, it seems that the pep button shows the mininum watt in ssb while the AVG shows the maximum... I think that they are place up side down somehow... Do you have any idea???

Hi M8 , i have the HP2 , Hp3 NS660 Daiwas , instead of using a radios power is there any other way to generate a type of more accurate REFERENCE power output, ie a signal generator ?you probably would have to boost the signal? PeaceFromOz 🇦🇺

What do you use to power this meter? how many amps? or do you just connect it directly to your 13.8 v power supply

4:09 The Diamond reads 2.8 watts. Its on the 20 watt scale? The selector switch shows reflected... Not forward. Better take a look again!

The PEP hold is 300 watts higher than the standard non hold PEP????? Any idea on how to adjust this?

Set to average not pep, correct?

Rubbish about 60% range being the most accurate. I actually built and calibrated the Bird watt meters. I have built countless Jeweled and Taut Band suspension meters. They are calibrated at full scale and must track within a certain tolerance or be rebuilt or scrapped.