Build your own Channel Master Monitenna

[jjlongworth]

About three weeks ago I posted a message looking for dimensions for an old Channel Master Monitenna. No one responded. Fortunately, I was able to finally get in touch with Kevin7777 who authored a thread a while ago about this antenna and he generously shared an AutoCad file that contained the critical dimensions. This was enough to get me started. By pure coincidence, I found one for sale about an hours drive away soon after receiving the dimensions from Kevin. I made the trip and bought it.

For those of you not familiar with the Monitenna, it was a truly broadband receive antenna. It's been a very long time since I've owned one, but I do remember it being a good performer. The antenna was discontinued about 20 years ago and I don't believe there is similar antenna on the market today. Since I've been disappointed in my discone, I was determined to build a replacement based on the original Monitenna design. Attached are plans that I wrote for building your own. I literally designed the new antenna side-by-side with the original. It requires that you be handy and resourceful. You must also have access to normal shop tools and know how to use them.

I have build 4 of these antennas using the original as a guide. I've double check dimensions and have included what I've learned into this document. I have not had an opportunity to test them yet, but I have no reason to believe that they won't perform as well as the original (or better). It is just too cold and I'm too old to be putting up antennas in the winter. That is a job for springtime.

Read the disclaimers before starting your build. Please be kind and let me know what you think.

Jim

 

[jjlongworth]

Hi... I'm glad to see that I got a few "likes" (thank you) and quite a few views for the plans I posted. No comments though :-(

I've made some minor tweaks, since I posted it, and have attached Rev C.

If I can locate either an AntennaCraft ST2 or a Radio Shack 20-044, I will consider writing plans for those (time permitting).

Jim

 

[N9JIG]

What info on the ST-2 do you need? I have some in my attic and a copy of the engineering specs.

 

[jjlongworth]

Thanks for the specs. As I mentioned, Kevin77777 had captured many of the overall dimensions for the Monitenna. That was a good start. But, by pure luck, I was able to locate an antenna to purchase as well. Having the antenna in my workshop, to refer too, made the job of designing a new version much easier. Without it, I would have been guessing at some of the features.

I've downloaded a bunch of photos of the ST2 and looks a little more complicated (with multiple insulators etc.). I can probably bring the photos into a program like Adobe Illustrator and manipulate the images to get an idea of what's going on, but it would be a bigger task without having the actual antenna.

 

[krokus]

If I can locate either an AntennaCraft ST2 or a Radio Shack 20-044, I will consider writing plans for those (time permitting).

Jim

Someone is selling a clone of the RS antenna. I have no idea if it is any good.

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[jjlongworth]

The facial expression on my profile picture says it all... That's a little steep.

 

[Blackink]

Hi... I'm glad to see that I got a few "likes" (thank you) and quite a few views for the plans I posted. No comments though :-(

I've made some minor tweaks, since I posted it, and have attached Rev C.

If I can locate either an AntennaCraft ST2 or a Radio Shack 20-044, I will consider writing plans for those (time permitting).

Jim

Nice work with the detailed instructions and pictures! Very well done. Thank You!!
I don't have the tools to make one but I'm hoping to see some feedback here on those that do build one from these directions.

 

[jjlongworth]

Thank you! I wasn't fishing for compliments, but I appreciate the feedback.

 

[RoninJoliet]

WOW, you must be a architect , those plans are fantastic.....I purchased three 5094A antennas 30 years ago....Two are still on my tower and one the top assembly wiggled off and landed in the ground in a wind straight up, good thing I wasn't standing out there but the remaining bottom portion is still up there and receiving the ILL-Digital 700mgz Starcom perfect using 60' of LMR400 attached to it.....lol....There the greatest ever made in my book....

 

[jjlongworth]

Thank you. I'm blushing....

Being a perfectionist is a curse. I've continued to think about ways to improve it and have a couple of ideas. I may post a Rev D if I implement them. - Jim

 

[trp2525]

If anyone is looking for a source for the 300-to-75 ohm balun matching transformer, you can order one directly from Channel Master. They have their CM-94444 "Outdoor Balun/Matching Transformer" (which also includes a weather boot) for $5.00 with FREE shipping included: Channel Master CM 94444 | TV Antenna Balun/Matching Transformer

Also, as an FYI, Channel Master sold a 5095A Monitenna in addition to the 5094 and 5094A. The 5094 was the original design (sold in the late 1970's) and only covered 4 bands (VHF-Low, VHF-High, UHF and UHF-T). The 5094A (which your very meticulous design plans cover) replaced the original 5094 in the late 1980's and covered 5 bands (VHF-Low, VHF-High, UHF, UHF-T and 800-912 MHz). The 5095A was a "Monitenna Kit" that included the 5094A 5-band antenna, 50 feet of RG-59U coax, a tri-mast mount and all necessary mounting hardware (see attached picture from the 5095A box).