Dusty 25 yr old garage stored Diamond D-130 antennas still usable?

[TrainsOfThought]

Advancing my retirement re-entry into the scanning hobby and GRAND rural reception experiment I'm wondering if these two (2) Diamond D-130 discone antennas stored in the garage eaves after 20+ years are still usable....I get back on the roof since 2000. These used to be on our city townhouse roof along with a Cushcraft ARX-2B Ringo for RAIL BAND (and starting to antenna experiment). Before erecting more advanced gain antenna I decided instead to pick up where I left off with these to establish a new blank slate.

These discones...ALL the major radials are intact (minus the upper vertical), no damage and everything is tight. I believe these are the NON-N coax connector w/RG8 coax from way back.

At this stage might I be better off purchasing (a) NEW Diamond D-130 discones with the N connector (I know is better) to start my project? Part of me hates to not use the old ones but starting a new, blank slate replacing with a new N connection seems logical in our rural situation.

Part of the larger project is also receiving marine band (on dedicated scanner) here on the shores of the Chesapeake Bay. Part of me thinks purchasing a new Cushcraft Ringo ARX-2B self-tuned to the marine band INSTEAD of a marine-built antenna would accomplish the same thing minus the exorbitant cost increase based on "marine".

Thanks all.

 

[CommRX]

I suppose it depends on the salt corrosion, but I would use them in a minute. Clean up the connector, throw on some dielectric grease and roll with it. If you decide to part with them, you can send them 125 miles south - I'll put them to use, as I'm picking up planes over you on a 20 year old Hustler 3 element I just put back in action. You can always replace them later if they do not perform as expected.

 

[mmckenna]

These discones...ALL the major radials are intact (minus the upper vertical), no damage and everything is tight. I believe these are the NON-N coax connector w/RG8 coax from way back.

If you have all the elements, and they are not broken, it's probably good. The only thing that would fail that would be an issue might be the insulator or the center pin of the UHF connector.
If you know how to use a multimeter, check for continuity from the center pin of the connector where the coax goes to the TOP ring of the antenna. It should show continuity. If it doesn't, then there's an issue.
Do the same test from the outer shield of the coax connector to the lower elements. Should show continuity.

Now, with everything disconnected and the elements NOT touching anything, check for continuity between the center pin of the coax connector and the outer shield of the connector.
There should NOT be continuity.

The concern is that the insulator between the upper disc and the lower elements might get damaged in storage. Unlikely, but it's an easy test.

Other than that, there is not much to them.

At this stage might I be better off purchasing (a) NEW Diamond D-130 discones with the N connector (I know is better) to start my project? Part of me hates to not use the old ones but starting a new, blank slate replacing with a new N connection seems logical in our rural situation.

I wouldn't.
Sure, the N connectors are a bit better at the higher frequencies. Even then, it's going to be hard to notice the difference. If the antennas work, use them. Just get coax with the correct connectors on the ends.

Make sure you waterproof the outdoor connections.

No reason these antennas should not work. I've had one up on my roof for about 10 years, and I'm a few miles in from the ocean. No issues with it.

Part of the larger project is also receiving marine band (on dedicated scanner) here on the shores of the Chesapeake Bay. Part of me thinks purchasing a new Cushcraft Ringo ARX-2B self-tuned to the marine band INSTEAD of a marine-built antenna would accomplish the same thing minus the exorbitant cost increase based on "marine".

Thanks all.

It will probably work fine.
I have an AIS receiver at one of my high sites at work. It shipped with the Sirio 5/8ths wave VHF antenna. It's been running fine since 2013 or so, no issues at all. I'd absolutely purchase one if I needed another. A reasonably priced antenna, and will work fine near the ocean. Get it up as high as you can, as that will dictate performance.

 

[wtp]

i would just replace the coax. even RG6 looks good.

 

[mmckenna]

These discones...ALL the major radials are intact (minus the upper vertical),

Unless you are specifically listening to low band VHF, the upper vertical isn't necessary. Just cap off the top when you install it to keep water from collecting inside there. It's ~probably~ a 3/8" x 24 thread, so a short bolt would work.

 

[iMONITOR]

These discones...ALL the major radials are intact (minus the upper vertical), no damage and everything is tight. I believe these are the NON-N coax connector w/RG8 coax from way back.

It's very common to delibertly remove the top antenna element for typical scanner radio use as unless you are monitoring VHF-Lo as mmckenna suggested. You should also remove the loading coil (circled in yellow).


The end result should look like this ]----->

 

[N9JIG]

I would also remove the elements and be sure that the contact points (where metal touches metal) is not corroded or tarnished. Be sure they are electrically sound. Be sure you have all the set-screws, they are easy to lose and replacements can be had at hardware stores. Be sure to get stainless steel ones if any replacements are needed.

Also check the SO239 to be sure it is electrically clean.

As long as these are OK the antenna should work great. They are mostly made of stainless steel so hold up well. I have a 25 year-old D130 in my attic, actually the third attic it has resided in. I also have a couple ST-2's that are even older and these are aluminum.

As for the coax: you are more likely to get improvement from new coax versus a new antenna. If the coax has been exposed to the elements the jacket can be damaged over time and water intrusion could occur. RG8, RG8X and RG6QS are all great coax for the D130.

 

[2006walt]

I have a related question. Have VHF/UHF ant to install in attic above garage. What cable should I use to run about 50 feet to rear of house? Temp in attic can go above 100 deg. Live in Fla. Should I use LMR400 or similar? I will operate VHF/UHF no more than 60 watts. Need cable to withstand hot temperatures. Thanks

 

[N9JIG]

RG8X or LMR400 should be fine at that short length.

 

[mmckenna]

Temp in attic can go above 100 deg.

That won't be an issue at all.

 

[majoco]

I don't know how old my discone is - but I removed it from a company office that we were demolishing in 1995! I asked first and they said 'no problem'. The office was built in the early 60's. The 'hub' is solid aluminium, the elements are reasonably thick tubing which were attached with self-tappers which I drilled out and replaced with nuts and bolts - and it still works a treat!

 

[merlin]

Old doesn't mean bad especially if installed properly in the first place.
Failures are usually at the coax connector if not weather proofed.
Coax doesn't go bad except water intrusion from cut sheathing or connector ends.
bends less than specified radius, kinks or crush points.
My discone has been up short of 3 years, old and used when I bought it.
All stainless steel construction, Hard to find today.
I havn.t looked, but when installed, the connector I packed with #4 compound then trying a seal with tape and a coating of 'FlexSeal'.
My Nano VNA shows no change at all coming up on 3 years.
I also packed the set screw hols with the compound because even the stainless can rust over time.
As mentioned, unless you have use for the loading coil/whip, I would remove it.
Cheers.