Yes -- In that picture, the top of the coil slopes or curves upwards to meet the 1/4" tube.

That tube is about 10" long, maybe 12".
And there's a set screw at the top of it, and an adjustable solid steel whip from there upwards.

Check the below pics, and you'll see the situation.
Mine is much older looking than that modern pic you sent, although it looks as if the assembly is much the same -
a steel tube crimped onto the top of the loading coil, and a setscrew/whip at the top of that tube.


http://wnc.bcca.org/IMG_3815.jpg

http://wnc.bcca.org/IMG_3816.jpg

One idea that just this second occured to me is that I probably have some scrap aluminum tubing around - rescued from an old TV antenna or something like that. Anything that's 1/4" ID would work OK

If the setscrew part at the top of the thin tubing would fit into a 1/4" ID aluminum t
and also over the stub you see at the top of the coil, that would be much more standard construction and easily hoseclamped together, as many 2meter antennas are built that way.

I hadn't thought about replacing the entire tube,

Until you got me thinking about how to describe the assembly to you, I'd not been thinking about the top part.

Now that I've considered this thing as a whole, I probably can find an entire replacement tube and just re-use the top stub with the setscrew and whip, and a clamp, and do the same 12" down at the top of the loading coil with another clamp.

More rigid aluminum tube should take to hose clamps a bit better.
The real problem is that thin crappy tubing Hustler uses there - looks just the same on the new antenna.

Something like the same tubing as is used on the spider legs should work great!

thanks for the inspiration and pushing me out of the box in my thinking!

You've got it --

By clamp nut do you mean a hose clamp?
Like this:

http://www.lowes.com/ProductDisplay?partNumber=267340-37672-884274&langId=-1&storeId=10151&productId=3234556&catalogId=10051&cmRelshp=req&rel=nofollow&cId=PDIO1

I don't know that I can find that in 1/4" diameters.

This, I can
http://www.nutsandbolts.com/4-hose-clamp-min-14-max-58-qty-10-p-360.html

But I noticed that all the other clamps on the antenna are the solid type with a nut and bolt
pulling the ends together.

I was thinking that maybe the type above from nutsandbolts isn't good for outdoor use, and would break after just a year or so, so I was trying to avoid that type of clamp and find something made with better thicker metal, yet able to hold a 1/4" sleeve onto a 1/4" shaft.


But if you think that nutsandbolts type of clamp would hold up well, I'll get one and use that -- it's about all I can think of.

yes- I'm talking about the top of the loading coil (thanks for the correction, yes it's not a trap)

And the replacements are on the order of $60-70 with shipping.

Until I'm sure the rest of the antenna is in excellent shape and loads up well, plus knowing what else I have to spend on the rest of my shack getting it going, I don't have that kind of money for this antenna..

I'm hoping to be a ham operator of the golden age of our hobby and be a bit more of a homebrewer, instead of just solving the problem with my checkbook like so many of the new kind of hams today seem to do.

The metal tube isn't threaded, and goes down over a plain stub on the top of the loading coil, no threading or setscrew or anything.

Hi all

I have a 5BTV with the RM-80S trap.
Among the several things I'm doing to clean and adjust it after 20 years in the air, before reinstallation,
I have to reattach the whip/stub section to the top of the 80M trap.

The section of the stub which attaches to the 80M trap is made out of thin metal, roughly the same kind of very thin rolled sheet metal that the external collapsible antennas on portable AM/FM radios/CD players used to be (most don't have external
antennas today, it seems)

That section now just falls off the top of the trap - very very loose after years.
I don't know if there was a pipe clamp or anything else holding that on.
It appears that it may only have been crimped in a press back in the day.
The diameter is only about 1/4 in or 1cm.

I can't get a pipe/hose clamp capable of going down to 1/4" diameter and being tight -

Does anyone have other ideas of how I could attach this in both mechanical and electrical means?

Being the kind of metal it is, I doubt seriously if it would solder, not to mention that would not be a good mechanical bond for mechanical stress for years outdoors.
By the way, the section shows the corrosion I have to remove and obviously, it's just stuck on there right now.
Comes off with the gentlest of tugs upwards.


See the picture.
http://wnc.bcca.org/RM-80S-whipsection.jpg

(http://wnc.bcca.org/RM-80S-whipsection.jpg)

Thanks, I'll watch out for one...

I'm looking for models of older 144Mhz rigs (mobile and HT) that have the ability to receive AM aircraft from 118Mhz upwards.

I'm not sure what the best way to find a listing of models which have that capability is - so I can look on Ebay for them.

I know my IC-2000H does it (although not all serial numbers do - I've got one that does, and one that won't actually output AM signals, though they appear on the S-meter. I'm told that is a ROM issue with later IC-2000H rigs when Icom removed the feature for the last production runs of that radio)

I know the IC-2200 radio does-

Anyone know of older Kenwood/Yaesu/other models that can receive 118Mhz-127Mhz aircraft AM signals?

I'd like to widen my search of models on Ebay--

thanks and 73 de KA4LFP

Yeah, I looked at pics of them online, and it seemed like the length was about half what the lower 6-leg spider was.

I think I'll try about 6" by 1/2 strips.

I go to a local metal scrapyard a lot looking for motors (my other mid life crisis is renovating old woodworking tools like my '48 Shopsmith 10ER or my 1935 Companion bandsaw)

So I'll probably be able to find the metal strips there lying on the ground.

I've seen enough aluminum tubing just lying on the ground waiting for the crusher to make a dozen 2 meter antennas or HF yagis.

Come to think of it, that might be the next project-- a 2m 14-element quad, made of all the scrap aluminum I can get there for just pennies.

Not as yet --

I sorta figured calling up a manufacturer and asking them how to homebrew a part they would rather sell me would be insulting to their salesperson on the phone at best...

Yes - I could just buy one, but I'd rather understand what that part does, why it has to be the dimensions it is, etc.

I won't learn anything if I just whip out a credit card to solve my problem.

Hi all -

I've got a 5btv that I hate to admit I've had for years, and I need to replace the top spider used for 75/80 meters.

Mine's completely gone - as I recall, it was only a hose clamp and three little pieces of stub metal to act as a ground plane or capacitor for the 75/80 meter trap and tipwire above it.

In keeping the spirit of ham radio of years now going away,
I want to homebrew a new one instead of acting like a lot of hams today and just whipping out a charge card and buying something instead of taking the time to make it and learn.

So --- I think there are three "radials" ? on the spider, from pictures I've seen.

Does anyone know how long they each should be?


Note - this is NOT the larger spider that's down lower and has six legs made out of 1/4" aluminum tubing.
This spider is only for 80M, and goes directly below the top coil when that option is added to the 4BTV
to make it into a 5BTV.

So here's an update, for anyone that can help -


After some experimenting, it seems that the problem is limited to the chassis of the radio.

If I didn't mention it before, I have two of these radios- one that does receive air band AM transmissions, and the new-used one that doesn't.

I swapped out the front ends, and both front ends experience the same problem when on the "newused" chassis.

Both front ends receive air band just fine when connected to the chassis that I've had for years.

I can't tell if there's any intelligence in the back half of the radio - don't appear to be any large many-pin SMT processor-looking chips. It sure does appear that all the "brains" is in the front part of the radio, not the back half. That's where all modifications are done, so far as I've been able to determine.

So I'm now wondering how it is that these radios would switch from AM to FM back in the receiver-stage section; thinking that perhaps something's wrong with a detector circuit such that it is "stuck" in FM mode, and won't switch to AM mode.

I recall from my long-ago General class studying that FM requires a different type of detector circuit, but I don't know exactly what the difference would be or how you'd switch from one to the other, especially in an automated fashion like these radios do.
My only FM-capable HF rig, it's a manual switch - just won't even get FM unless I move the switch.

You'd think that'd be in the programming, but I don't think there's any intelligence in the chassis.


Any chance that someone can clue me in as to what might be wrong in the non-digital portion of the radio?

I would agree -
It's crazy what accessories and such are going for, just because out-of-area pricing has driven everything up --- a replacement microphone for a 10 year old rig was more than 75% of the value of the same rig being sold -- and there were multiples of each item, so it's not that they were rare.


People just think that they should get close to what they paid, no matter what the age of the equipment.

It always amazed me to see people selling 15 year old rigs with the original box and plastic wrap, and even the plastic protection
sheets stuck back on -- selling them for 90% of the original price.

Who would expect to sell a car for 90% of new after five years of driving it?
But people expect radios to be worth 80% of their $800 new price after 10 years?

Thanks for the incredibly quick response and idea..

I downloaded a copy of the manual from here:
http://www.radioamateur.eu/schemi/IC2000H_user.pdf

and I don't see an a/f option.

Don't see it under "set" either, unless I'm not in the right mode or something -

But that's the direction I'm trying to go -- finding some option not set that needs to be..
It's acting so much like it wants to receive this, and has no other problems that I'm really suspicious of some programming issue..

I'm going to try to compare the channel setup on my working IC-2000H with this one - which will require taking one radio to the other, somehow, and powering both up...

Any ideas you see in the manual that I didn't see for that "enable AM" option?

73, Tim

Hi folks --

I have a little bit of a strange problem.

I have an IC-2000H that works OK on FM.
I can program repeaters, work simplex, and get
great reports -- both on how I sound and how the other side sounds to me.

But the IC-2000H also supports extended receive, most notably in the aviation band - 120-122 Mhz, as many of you will know.

What's weird?
The radio absolutely REFUSES to receive any of those AM signals from the local airport.
I have another IC-2000H in my truck which does just fine.

The S-meter shows a full-strength signal on the various freqs used locally --
but not one sound comes out of the speaker.

It's obviously receiving the signal, since the S-meter shows the signal received.
It's also muting the speaker - or at least a click is heard the minute I change to an "air" channel.
So the audio amp is working -- but there's just absolutely no AM signal getting to it.

I've reset the rig several times, hoping to clear a stuck bit in a register or something-  but I'm beginning to think something's wrong with the circuits that do the AM receiving.

Any ideas?

I have an FT-757 with a problem I'd like to ask about-
The radio receives fine, but will not 'key down' even into a dummy load. The 'on air' light blinks, the receiver goes off, the transmitter appears to be on for a second or so (needles on my MFJ tuner twitch)
and it goes back to receive mode.

this behaviour is apparent with both the mic in SSB, a key in CW, or the back-of-radio PTT jack in either mode.

I have recently received the radio via UPS shipment, and have tried to check it out for loose connections, etc. I don't know the radio's history (bought it used two weeks ago).

Anyone have ideas on where to begin on this one?
I have manuals and schematics if anyone wants to point out any spots to start checking via that documentation.

I have an FT-757 with a problem I'd like to ask about-
The radio receives fine, but will not 'key down' even into a dummy load. The 'on air' light blinks, the receiver goes off, the transmitter appears to be on for a second or so (needles on my MFJ tuner twitch)
and it goes back to receive mode.

this behaviour is apparent with both the mic in SSB, a key in CW, or the back-of-radio PTT jack in either mode.

I have recently received the radio via UPS shipment, and have tried to check it out for loose connections, etc. I don't know the radio's history (bought it used two weeks ago).

Anyone have ideas on where to begin on this one?
I have manuals and schematics if anyone wants to point out any spots to start checking via that documentation.


I would appreciate it if interested people would also email me directly at tim@pisgah.new-era.com