NASA navtex aerial - glue?

[Billjratt]

NASA navtex dual freq white pillar aerial.
Trod on the damned thing - don't ask! and broke the flimsy mounting bracket.
Have tried several different types of glue, but none are compatible with the plastic the bracket is made from.

My next attempt will be a great blob of P70 which almost guarantees a fix, but will be less than aesthetically pleasing.

If you have successfully fixed one of these, what did you use please?

Save me from myself!

 

[awol]

Throw it away, attach inner of co-ax to rigging, ideally below decks.

 

[davidej]

could try the solvent glue that plumbers use to fix wastepipes.

ABS??

 

[Billjratt]

Rigging? No. Tell me about the glue.
IF anyone takes AWOLs advice they must use a capacitor to block the DC.

Thanks Davidj I'll ask the guys who happen to be working in the house as we speak!
Edit : ask for solvent cement, he says. So that's what I'll do (and report results)


That was a speedy resolution.

Unless it breaks again.

 

[Sandyman]

NASA navtex dual freq white pillar aerial.
Trod on the damned thing - don't ask! and broke the flimsy mounting bracket.
Have tried several different types of glue, but none are compatible with the plastic the bracket is made from.

My next attempt will be a great blob of P70 which almost guarantees a fix, but will be less than aesthetically pleasing.

If you have successfully fixed one of these, what did you use please?

Save me from myself!

Plumbers glue as someone called it wont work. Not in the long run. I broke mine a couple of years ago & fixed it with standard superglue. Still going fine.

 

[pvb]

Throw it away, attach inner of co-ax to rigging, ideally below decks.

Isn't the Nasa antenna an active antenna??

 

[Conachair]

Rigging? No. Tell me about the glue.
IF anyone takes AWOLs advice they must use a capacitor to block the DC.

Not heard that before, where would the DC come from?

 

[lenseman]

Isn't the Nasa antenna an active antenna??

Some are, some aren't. Two different types made my NASA!

 

[lenseman]

Not heard that before, where would the DC come from?

Some NASA antennas are active. Others are just antennas. They look identical but believe they have a coloured band on the base to differentiate one from the other.

 

[pvb]

Some are, some aren't. Two different types made my NASA!

I thought the dual frequency one was an active antenna.

 

[awol]

The active aerial carries a 5v dc isolated voltage. Despite that it will work happily with a long enough wire - somewhere about 10m should do. After the active aerial was used as a handhold and and then dragged through the water for a night my NASA Clipper has been running for the last few years connected below decks to a stanchion base, connected to the pulpit, connected to the forestay, connected to the mast and all the rest. It seems to work fine, particularly since Malin Head started putting out the Met Office forecasts.

 

[Sandyman]

So whats in an aerial to make it active ? Just a pre-amp ?

 

[prv]

The brackets on Nasa's rod aerials are universally ****. I think it's true to say that on every boat I've ever chartered with one fitted, the bracket had been broken. (One boat had two, for a Navtex and a Weatherman RTTY receiver, and both had been broken and repaired.)

When we bought Kindred Spirit, the Navtex aerial had been securely mounted using a pair of custom stainless brackets. I asked Mr Nasa at the boat show, and he said being surrounded by a metal ring in this way shouldn't have any effect on its function.

Pete

 

[Billjratt]

An active antenna has a masthead amplifier in the antenna package. It is powered from the display unit in exactly the same way your TV dish LNB is fed.
In order to stop DC volts appearing on your rigging and causing electrolysis problems, a small capacitor should be inserted in series with the coax connection to the stanchion or whatever.
I'm not going to do that as HF stuff has been waiting to come aboard for some time.

Thanks PRV et al. I'd been toying with the idea of some SS bits. We'll see.
Shame I drilled cable holes just where I did. (on the wheelhouse roof, but I dance about up there while 'doing' the main.)
I seem to be receiving OK with the ae horizontal, perhaps it would be less vulnerable mounted that way. Need to try the same with the weatherman.

Edit again: now designing a spring-back mount.

 

[Conachair]

An active antenna has a masthead amplifier in the antenna package. It is powered from the display unit in exactly the same way your TV dish LNB is fed.

Ah, I see DC coming out of the reciever , not going in.

I've a nasa navtex engine connected to a ham radio dipole going up to the mast head which has been picking up from norway recently amongst others. That's moored up a few feet from a massive office block in middle of london. Was fairly useless with the (not active) aerial which came with it.

 

[Babylon]

I trashed mine (both of them at once) by falling against the pushpit. I just got some cable-ties and made lashings at the base of the plastic tubes to hold them to the s/s rail. That was three years ago and they've worked as well as they ever did since then.

 

[Gwylan]

NAVTEX & rigging

Rigging? No. Tell me about the glue.
IF anyone takes AWOLs advice they must use a capacitor to block the DC.

Thanks Davidj I'll ask the guys who happen to be working in the house as we speak!
Edit : ask for solvent cement, he says. So that's what I'll do (and report results)


That was a speedy resolution.

Unless it breaks again.

What DC? What capacitor?
We do use the rigging and it all works well - bringing in signals without a problem.

 

[lenseman]

If the worst comes to the worst, fabricate a completely new plastic case out if white 1¼" poly pipe. You only need an off-cut about 6" long and as explained by others above, solvent glue and a couple of white 1¼" blanking caps from your local plumbers finishes off the repair. Kitchen sink waste is too wide (1½") bathroom sink waste is 1¼" and is perfect.

Plumbers merchants can also supply white wall mounting brackets which can also be used to mount the "poly-Pipe Antenna".

 

[Twister_Ken]

I broke one on Indigo and the replacement filled up with water somehow. Installed the third below decks in a tucked-away corner. It worked fine - if only I could say the same about the NASA Navtex Pro receiver.

 

[pvb]

I've never understood why people buy Nasa stuff in the first place. It's horribly designed, has lousy literature, and has poor performance. Is it the irresistible appeal of a "bargain"?