Moonraker 4 project begins

[321 treeclimber]

I was given a beam antenna and so starts the restoration and installation of a well kept and intact moonraker 4. Taken down in the late 70s, I'm told, then wrapped up and stored in an attic til now. I've decided to put it on a rohn 40'ft tower so i went ahead and just this weekend poured a concrete base for this tower, which i got in trade of some tree work last year. The base was simple, cut the ends out of a 55 gallon drum, dig a hole so the edge of the drum sticks up out of the ground about 4 inches. drop in a 4 inch layer of # 2 stone and fill with concrete. Level top. Done. Simple yes...easy,NO. Thats another story. Any way thats where its at. Next phase is antenna resto. 321

[cbrown]

Is it a freestanding tower, or is it guyed? For example, a 40' Rohn 25G self supported tower requires a concrete base size of 6' x 6' x 4'. The guyed version is 3' x 3' x 4' (I believe). A typical 55 gallon drum is 1.9' in diameter and 2.79' in height. So it's no where near the specification Rohn calls for.

if it were me, and I was putting up a Moonraker 4, I'd use what Rohn calls out for, especially if you get ice and/or wind in your area. Also, I'd use a fairly good rotator as the Moonraker has a large wind load area.

[321 treeclimber]

10-4 CB, THIS WILL BE GUYED. i also poured a 6"inch by 6'ft. Square pad around it. Made a nice service area for future maintenance. Haven't looked at rotors yet, any particular brand or type i should look at ? 321

[cbrown]

Sorry, I can't help on newer rotators, still have my Ham IV.

[321 treeclimber]

Roger that. I'm sure there's something good out there. Looking forward to the actual antenna clean up. Will need new reflector wire.

[cbrown]

I got this from Jay in the Mojave a while ago, just thought I'd post it for a heads up on that reflector wire idea.

The Moonraker 4 is a great beam antenna. It was designed around inexpensive parts, but was very well designed and operated very well. Having good gain and great rejection.

There are mods out there that install more reflector wires on the quad reflector. But this will only degrade the Moonraker 4 performance big time. This being proven with many experiences, and seeing the beams pattern be distorted from Eznec, an antenna molding program.

The best thing that you can do is use good coax like the LMR-400 and install the Moonraker 4 on a tower, getting the antenna as high as possible, with a good rotor, like a HY-Gain 4 or Tailtwister Rotor.

[321 treeclimber]

Awesome info! I will restore as was 40+ years ago. I remember as a kid the guy down the street got one and it was magic! Hope it still has that magic. 321

[cbrown]

Jul 10, 2019 20:31:24 GMT -5 321 treeclimber said:

Awesome info! I will restore as was 40+ years ago. I remember as a kid the guy down the street got one and it was magic! Hope it still has that magic. 321

Good luck, and if you have any questions, ask away.

[321 treeclimber]

Roger that cb. Im sure I'll have at least a few questions. Im going to continue tower resto for now and along the way order the coax, rotator and control and all the cable and hardware. Figure I'll be assembling the beam by mid September.

[oldgeezer]

A Ham IV rotor would work well. It handles 15 sq ft of antenna wind load. I think moonraker is 5 sq ft wind load. Rebuilt Ham IV (called Ham 4 at times) on ebay for under $400.

[ytradio]

I turned mine with a CDE-44, a ham friend who had a TV shop ordered for me along with the beam. At the time, he claimed it would be able to turn stacked Moonracker IV's. I never had any problem, and still use this same rotor today. It is however rated in the original literature for only 2 sq ft. I would not want to try stacked beams, but I also think 2 sq ft is under rated. Hy-gain bought out CDE, and IMO the CD-45II is a close second. It is rated for 8.5 sq ft wind load. If buying a new rotator for that antenna, the 45II would be what I would go with.

[321 treeclimber]

10-4 YT, i will look it up. Any ideas on an outlet for this brand? 321

[ytradio]

DX Engineering I know for sure, probably Texas Tower and Universal Radio also.

[321 treeclimber]

Yep'r dx engineering has been a great resource for me. All of my coax comes from them. Ok I'll see what they have. Thnx again. 321

[321 treeclimber]

Ok but they show it out of stock. I'll call later. 479.00 not bad.

[oldgeezer]

A CD45II rotor would also work, but the Ham IV would hold up to about any storm and a Hurricane up to category II.

[321 treeclimber]

Wow ! I dont think the antenna would survive that even if the rotator did !

[cbrown]

Jul 23, 2019 9:44:39 GMT -5 321 treeclimber said:

Wow ! I dont think the antenna would survive that even if the rotator did !

Not true. I had a Moonraker VI make it through a Cat 2 storm in the 70's, and both the Ham IV and the Moonraker came though it fine.

[321 treeclimber]

Very good to know I love this antenna and I hope it serves me well for a long time I've been waiting a long time to do this

[oldgeezer]

You will be able to hear a flea fart in CA!

[321 treeclimber]

Hahaha yep'r. Hey geezer started wiring up a d104 tug8 last night. Hi-z mic arrangement. For that courier 23+.

[oldgeezer]

Amplified D-104? That will really make it sing. Produced 20 watts peak out with non-amplified microphone.

[321 treeclimber]

Its that or a turner 3. I'll start with the d104.

[ytradio]

If you can get a good HamIV for the price geezer told you, I would go that way.

[evjr]

Jul 23, 2019 7:26:52 GMT -5 ytradio said:

DX Engineering I know for sure, probably Texas Tower and Universal Radio also.

I always use a #12 solid wire on the reflection element as it does seem to improve rejection some what. Ambushman

[321 treeclimber]

10-4 ok that's good advice. I will move in that direction. Thanks much appreciated .