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Reviews For: K4DPK PEP Adapter

Category: SWR & Wattmeters & Dummy Loads

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Review Summary For : K4DPK PEP Adapter
Reviews: 28MSRP: 30
Make your Drake, Bird, Collins, Daiwa, most other wattmeters read PEAK ENVELOPE POWER. Quick, easy hookup.
Product is in production
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# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
W9MT Rating: 2023-08-26
I both two modules for two different meter types Time Owned: 0 to 3 months.
The Drake W4 "deluxe" model literally installs with one resistor clip going to the meter terminal and two solder splices. It comes with the PEP module, prewired DPDT mini toggle switch and phono female (for DC power) pre-mounted on a sheet metal flange and all wired up.

The L-shaped flange simply mounts under two existing self tapping screws that hold on the top cover of the W4's directional coupler.

This was literally a five minute job, 10 minutes if you want to make the splices pretty with shrink tubing like I did. It was well worth the $55 price tag.

Calibration is a breeze requiring only one trimpot to be set to the same 100W level in Peak (PEP) mode that the meter also reads in Average mode. Your radio is the 100W RF source. If you want a different decay time rather than Phil's preset speed, you can play with the adjustment for the 2nd trimpot for changing the Decay speed. (I didn't. Maybe I will in the future, but I'm leaving it alone for now.)

I also own a Sola (now Coaxial Dynamics) Bird 43 clone Wattmeter (uses the same slugs as a Bird does, and vice versa). I bought the universal kit to add Peak reading mode to what is usually just an Average RF power reading meter. While I do plan to do the mod to that meter, it will require some up-front planning to determine the best places to mount the Peak/Average toggle switch, the module itself, and also the DC power jack. I may change Phil's phono female to a standard 2.1mm coaxial power receptacle that a 12VDC wall wart can readily plug into. Since judicious locating and drilling will be necessary, I'd like the job to look professional, rather than a hack job. Buying Phil's $35 universal module simplifies this installation job to just attending to the esthetics, rather than having to do a "ground-up design" and installation.

The other nice thing about Phil's design is that the 10 turn trimpots for Calibration and Decay can accommodate a variety of microamp full scale deflection meters with the one pot calibration setting. Decay speed in Peak/PEP mode is a matter of taste suitable to your operating style.

Both the W4 and Bird-type RF Wattmeters will still work in Average RF mode without the need for DC power. It's only in Peak/PEP mode that Phil's two stage op-amp circuit comes into play where external 12 Volt nominal DC power is needed.

Buying both at one time also saved me on the shipping costs. It was a flat $5 to get both within a few days via USPS with tracking.

I'm a happy customer with the install on my Drake W4. It really enhanced what was already a fine product. I look forward to making my Sola lab grade meter also "even better". Phil, K4DPK, has been making these for years and they're well worth the money over rolling your own.
N5XJT Rating: 2021-05-23
Great Product - Great Customer Service Time Owned: 0 to 3 months.
Easily installed on my W4 and Phil is a great guy to do business with. Highly recommend!
K6CTA Rating: 2021-03-02
Nice Addition Time Owned: 0 to 3 months.
A nice addition to my W4. Simple and functional. Phil was quick to respond to my email(s) and it was shipped promptly.
K0CWO Rating: 2021-02-23
Installed in MFJ-998 Time Owned: more than 12 months.
Very worthwhile addition to this tuner. Easy install and has worked flawlessly for 5 years!
VE3GLA Rating: 2021-02-22
excellent improvement for my W4 Time Owned: 0 to 3 months.
I love my W4 watt meters ( I have 2) but unfortunately they were designed to only read average power. I recently added K4DPK's PEP modification to one of them and it works great! Now I love that W4 more than ever. The kit only took a couple of minutes to install. I'm going to order another kit soon for my other W4.
W4PIG Rating: 2021-01-10
EXCELLENT Time Owned: 0 to 3 months.
K6RQR Rating: 2020-09-02
Excellent product Time Owned: 0 to 3 months.
I was interested in whether I could add the ability to measure PEP on the meter of my classic Johnson Matchbox antenna tuner. I emailed Phil and he said that it was quite possible so I ordered his Universal PEP adapter. It arrived in a strong box and had instructions and an explanation of how it worked and info about the calibration procedure. I did have one question about the wiring of the unit and Phil answered it quickly.
I thought I would have to order an DPDT switch and external DC power jack but they were included with the unit which was pre-wired and tested.
I installed the adapter and decided to put the DPDT switch on the rear panel at the top so I could reach it easily. It has two positions - Average and PEP.
I then followed the steps to checking the performance and the meter now shows PEP power and appears to be well calibrated. I can "tweak" it later if I want. One thing I appreciate is that Phil made the lengths of wire that come from the adapter long enough to accommodate the dimensions of my Matchbox.
I am very pleased with this purchase and I always enjoy modding my gear to make it work better. I recommend that if you have a regular SWR/Power meter and would like to add PEP readings contact Phil and let him know what you have in mind. I have already recommended this unit to a friend of mine who wants to add PEP measurement to his Collins wattmeter.

Bruce K6RQR
K4SUE Rating: 2020-03-21
Great way to upgrade passive 'PEP' wattmeters Time Owned: 3 to 6 months.
Ordered this for my MFJ 962D tuner. The tuner is a good tuner but the watt meter leaves a lot to be desired, especially in the peak mode. Like a lot of cheap watt meters, it relies on the passive method of charging a capacitor, which cannot keep up with PEP. I opted to drive a 12VDC relay from the lamp bulb which performs the switching function. So, with the lamp off, the meter functions as MFJ designed it and with the lamp on and the peak/avg switch in the avg position, peak power is read thru the DPK adaptor. Accurate and easy to set up/calibrate.
N4GKS Rating: 2019-03-05
Works Great Time Owned: 0 to 3 months.
Bought this for my Drake W4. I got the one with the mount and toggle switch. After installing and calibration, it works like a champ. Thanks, Phil and 73.
W4MAC Rating: 2018-03-12
Clean, Compact, & Works Time Owned: 0 to 3 months.
I just put this PEP kit in my Drake MN-2000 tuner so I could ditch the MFJ out board meter. Easy to install, simple directions with a pic for those of us who hate to read. Thanks for a product that works as advertised.