Best Antenna i ever owned

[mrkelso]

Is the Madol Action Hunter AH210R metal telescopic all black version. I have this baby hooked to my Uniden 346XT via a shot clip on and using a BNC to SMA adaptor clipped to a shelf in my Bedroom. This "LARGE for a Portable antenna" is pulling in signals from way far away where the stock antenna didn't hear squat. I think this may be discontinued now but i still see them available on ebay. The real deal is all black metal. There are knockoffs so know what you are buying if decide to try it.
Note: I would not walk around with this thing attached directly to my portable.

Very durable construction.

 

[br0adband]

I had searched long and hard, high and low, outside and inside, and I finally tracked down an actual Maldol AL-500H, the famed dual band VHF/UHF airband (CivAir and MilAir) antenna recently, but when if finally arrived after wanting one for so long all I can is how shocked I am at the performance which is for the most part non-existent whatsoever. After seeing so many favorable reviews of it and spending over a year scouring boards, forums, websites, eBay, craigslist, putting out feelers with friends to help in the search, I'm really disappointed and I've yet to be able to figure out what's wrong with it.

I talked with hertzian (another member here) in PMs about my luck with this thing and even he appears to be somewhat stumped. The whip itself is removable with a hex tuning screw so when I do remove it and attach it to a BNC input on my pigtail attached to my RTL stick I do get signals, but they incredibly weak in response overall (using my trusty Diamond RH-C77A in the same test gets me the expected levels of signals).

So then I started suspecting that perhaps there was something wrong inside the base of the AL-500H so I used a makeshift but functional continuity tester from the BNC center conductor to the end point where the whip is attached and was very dismayed to see nothing at all, no closed circuit, just wide open and now I'm really stumped. I suppose it's possible it's just defective, but when attached properly (whip screwed into place, then attached to the BNC pigtail) I just get hardly anything at all, inside or out - the RH-C77A in the same situation pulls in what I expect to hear and the AL-500H is "deaf" for all practical purposes.

Pretty sure it's not a fake either (that's hertzian's opinion as well based on the pics I shared with him) so I guess it's just broke-dead and nothing I can do about it.

Having said that, best antenna I've ever owned overall would be a fairly even tie between the Radio Shack 800 MHz and the Diamond RH-C77A so far. Had high hopes for this Maldol but... well, there goes that idea.

I might have to look for one of those that the OP just mentioned, had never seen that one specifically but I still need to find a telescopic model at some point, can't hurt to track one of those down I guess.

mrkelso: if you happen upon one on eBay anytime, drop me a PM will ya?

 

[prcguy]

I have an AL-500H and it does work noticeably better than any stock scanner duck or even the Austin Condor on VHF and UHF air. Sounds like something is broken in yours.
prcguy

I had searched long and hard, high and low, outside and inside, and I finally tracked down an actual Maldol AL-500H, the famed dual band VHF/UHF airband (CivAir and MilAir) antenna recently, but when if finally arrived after wanting one for so long all I can is how shocked I am at the performance which is for the most part non-existent whatsoever. After seeing so many favorable reviews of it and spending over a year scouring boards, forums, websites, eBay, craigslist, putting out feelers with friends to help in the search, I'm really disappointed and I've yet to be able to figure out what's wrong with it.

I talked with hertzian (another member here) in PMs about my luck with this thing and even he appears to be somewhat stumped. The whip itself is removable with a hex tuning screw so when I do remove it and attach it to a BNC input on my pigtail attached to my RTL stick I do get signals, but they incredibly weak in response overall (using my trusty Diamond RH-C77A in the same test gets me the expected levels of signals).

So then I started suspecting that perhaps there was something wrong inside the base of the AL-500H so I used a makeshift but functional continuity tester from the BNC center conductor to the end point where the whip is attached and was very dismayed to see nothing at all, no closed circuit, just wide open and now I'm really stumped. I suppose it's possible it's just defective, but when attached properly (whip screwed into place, then attached to the BNC pigtail) I just get hardly anything at all, inside or out - the RH-C77A in the same situation pulls in what I expect to hear and the AL-500H is "deaf" for all practical purposes.

Pretty sure it's not a fake either (that's hertzian's opinion as well based on the pics I shared with him) so I guess it's just broke-dead and nothing I can do about it.

Having said that, best antenna I've ever owned overall would be a fairly even tie between the Radio Shack 800 MHz and the Diamond RH-C77A so far. Had high hopes for this Maldol but... well, there goes that idea.

I might have to look for one of those that the OP just mentioned, had never seen that one specifically but I still need to find a telescopic model at some point, can't hurt to track one of those down I guess.

mrkelso: if you happen upon one on eBay anytime, drop me a PM will ya?

 

[br0adband]

Yah, it's a shame too 'cause I wanted one so bad hence me continually looking for it for so long and then getting it and, well, bleh.

Take a peek at this gallery and tell me if you think it's potentially a fake (as those are known to exist from what I've read in my research). This thing is fairly heavy at the base so I'm guessing it's got a lot of brass in there but I have no idea what else, all I do know is it just seems to not pull in much of anything at all compared to putting my RH-C77A on the same receiver in the same exact location/spot and tuning the same frequency.

http://img212.imagevenue.com/gallery/loc1100/44_1005_1394415383-15.php

I appreciate any input, I don't know any other method to test an antenna like this save for attaching it to a tuner and punching in a frequency. I figured the continuity tester would show "something" but hertzian said he disassembled one of his (meaning removing the whip) and then checking the same thing and said he got nothing as well and surmised it could have a diode inside the base blocking DC current - it's just odd to me I suppose.

Wish it worked better, of course, guess we all get duds sometimes.

 

[N9JCQ]

I have to agree with PRC as well. I think your 500H is kaput. I have the AL-500H and it makes a significant difference over the RH-77 in terms of reception here in the Chicago area on my Yupiteru 7100, RS Pro-43 and Uniden 396t for aviation purposes, which is what it is designed for. I have noticed the Comet AB-50H Air Band(RX 118-135/230-360Mhz) listed on ebay for almost $80.00. It looks physically like the Maldol, but no way am I paying $80 for a portable scanner antenna.

 

[eorange]

I have an RH77CA (almost 16 years old), and an AL-500 from about 9 years ago. They perform exactly the same on airband, for me.

 

[LIScanner101]

I appreciate any input, I don't know any other method to test an antenna like this save for attaching it to a tuner and punching in a frequency. I figured the continuity tester would show "something" but hertzian said he disassembled one of his (meaning removing the whip) and then checking the same thing and said he got nothing as well and surmised it could have a diode inside the base blocking DC current - it's just odd to me I suppose.

Maybe it's not a diode, but a capacitor instead? An open OR good capacitor would read like an open circuit on a regular DMM. Do you have a capacitance meter to check it on? Maybe a blown cap? Problem is even if it you determine that that's what's wrong with it I have no idea how you would be able to access the bad cap to replace it

 

[br0adband]

It's the weirdest thing I think I've ever encountered with respect to antennas, definitely. As for testing it "properly" I don't even own a multimeter so there goes that idea, someday I'll actually remember to buy one - even a cheap $10-20 model - just to have around.

I have no idea how the base is assembled on this thing, I've attempted to disassemble it by twisting (assuming it's all screwed together in some fashion) and has zero success, nor is there a way to screw off the BNC end either. Most BNC antennas will have an area (when you pull the BNC outer ring down as far as it will go) where you can insert a very thin crescent wrench, like credit card thickness, and then unscrew the connector assembly but this one doesn't so there goes that idea.

Thing is this: if you have any type of receiver, any at all of any kind, and you touch the antenna connector with any kind of metallic object, you'll typically get some kind of electrical activity - on an SDR setup that would translate into activity on the spectrum, be it a change in the noise floor (the most common thing because you've just added something to the circuit) or a momentary "spike" of signal. The sheer act of making an electrical connection of any kind translates into something you can visually see on the spectrum.

Now, with my SDR setup (typical RTL stick using an MCX to BNC pigtail), if I touch the inner connector on the BNC end with anything that's metallic at all, even something as innocuous as a thumbtack, I'll instantly see some activity on the spectrum, regardless of what I use. I've got several antennas around here (RH-C77A, RS 800, a couple of plain old telescopic whips, even random lengths of coat hangers, razor blades, screwdrivers, paperclips, etc) and whenever I make physical contact with that center conductor on the BNC end it always shows something on the spectrum without fail.

However, when I attach the AL-500H I get nothing, and I mean absolutely nothing - it's like it's not even being connected. I figured that perhaps, just maybe perhaps the BNC pin on the AL-500H is thinner than normal for some reason and it was being inserted into the BNC end of the pigtail so precisely that it wasn't even making contact with the BNC inner conductor at all (we're talking a few microns of space but no physical connection) so I took a tiny piece of aluminum foil and did a single wrap around the center pin on the AL-500H, still no apparent electrical connection at all.

And here's where it truly gets strange: if I put a paperclip in the BNC end of the pigtail I instantly get a signal of some kind (even readable on some frequencies, go figure) and then hold the AL-500H in such a manner where I can use the paperclip to touch the center conductor of the antenna - lo and behold I get signal, weak, but I get signal that is of higher strength than just using the paperclip itself (like going from -88 dBi to -82 dBi or something similar).

Go figure.

But whenever that AL-500H is directly attached to the pigtail, I would swear that it's like a null and void of some kind, it's not even acting like a dummy load showing any electrical contact whatsoever, it's truly bizarre. Tried 3 different variations of attaching it to the pigtail using coax and BNC/F connectors, no go. Tried hooking it to an old Radio Shack 100 channel purely conventional scanner that barely works in most respects and get basically nothing - remove the AL-500H and put on the RH-C77A or the RS 800, wham, instant signal.

Wish I could tear this thing apart now but I suppose it's a lost cause... just too weird, I swear.

 

[LIScanner101]

It almost seems like the center conductor is shorted to the shell of the BNC. This would result in no net/measurable effect when connecting the antenna to any of your scanners. The reason I say this is because of your observation here:

“…if I put a paperclip in the BNC end of the pigtail I instantly get a signal of some kind (even readable on some frequencies, go figure) and then hold the AL-500H in such a manner where I can use the paperclip to touch the center conductor of the antenna - lo and behold I get signal, weak, but I get signal that is of higher strength than just using the paperclip itself (like going from -88 dBi to -82 dBi or something similar).”

If you’re holding the antenna with your bare hands, and manage to somehow create contact between the antenna’s BNC pin and the paperclip, you’re basically connecting a complex “antenna” to whatever radio it’s connected to. The “antenna” consists of the AL-500H and your body (which is weakly connected to the antenna rod via the salt content of any slight amount of perspiration on your fingertips). Assuming your feet have some decent resistance to earth ground, your body is essentially “floating”, so you become part of the “antenna”. You and the AL-500H “add” to the reception capabilities of the paperclip, which is why you see a very slight improvement when you do this.

However, as soon as you connect the antenna directly to your scanner by using its BNC connector, you instantly shunt the center conductor to ground via the short that I SUSPECT is inside the antenna.

This is the only thing I can think of.

Can you borrow somebody’s DMM and check for a short between the BNC pin & shell?

 

[br0adband]

Yep, that's why I would hold the antenna base using either some paper or even the plastic packaging the AL-500H came in to ensure there was no direct contact with my skin, still zip-zilch-zero activity. Having said that, I did note that when I touch(ed) the paperclip to the body of the antenna base or the BNC (which should technically be the ground itself) there was activity on the spectrum so perhaps that's just what's wrong: the whole assembly is shorted out at some place, and since I can't seem to figure out how to disassemble the base itself then it's beyond repair.

I've done everything I am capable of doing to figure it out and I've gotten nowhere so it's just a done deal at this point. hertzian had suggested that perhaps a previous owner (I have no idea if the person I got it from is the only previous owner, just for clarification, it was advertised as new and unused when I found it and made the purchase, might be true, might not) had attempted to use it for transmission purposes and blown something out which to me seems plausible to some degree I suppose.

Either way I'm pretty much done with it, was thinking about taking it to AES here in Las Vegas and asking them to check it out, they're obviously more experienced with such hardware or at least they'd be able to attach it to a proper modern scanner (the old Realistic I have is like 20+ years old and it has most certainly seen better days, it could just be insensitive to airband frequencies, period) and give me some idea of whether it's toast or not.

I suppose that's my only hope at this point with respect to this particular situation. Anyway, I apologize for rambling on in this thread, it's obviously off-topic with my babbling, and thanks for the input, folks.

 

[LIScanner101]

Yep, that's why I would hold the antenna base using either some paper or even the plastic packaging the AL-500H came in to ensure there was no direct contact with my skin, still zip-zilch-zero activity.

Having said that, I did note that when I touch(ed) the paperclip to the body of the antenna base or the BNC (which should technically be the ground itself) there was activity on the spectrum so perhaps that's just what's wrong: the whole assembly is shorted out at some place, and since I can't seem to figure out how to disassemble the base itself then it's beyond repair.

Sounds like we’re on the same page here. If the antenna is shorted internally then you’re going to see some effect when you touch the BNC shell to the paperclip because the whole thing is just one big metal rod at that point.

Either way I'm pretty much done with it, was thinking about taking it to AES here in Las Vegas and asking them to check it out, they're obviously more experienced with such hardware or at least they'd be able to attach it to a proper modern scanner (the old Realistic I have is like 20+ years old and it has most certainly seen better days, it could just be insensitive to airband frequencies, period) and give me some idea of whether it's toast or not.

I used to work in a place that made portable medical x-ray equipment. We used to sneak and take x-ray shots of all sorts of things. Wish I still worked there, I’d offer to x-ray the antenna for you….!!

I suppose that's my only hope at this point with respect to this particular situation. Anyway, I apologize for rambling on in this thread, it's obviously off-topic with my babbling, and thanks for the input, folks.

Hey, no worries at least on my part, it was a cool discussion

 

[br0adband]

Final post about this AL-500H:

So I got to AES, first guy was relatively clueless about what I was asking (just wanted to attach the antenna to a scanner/receiver and tune an airband frequency or two and see if there was any noticeable but definitive reception issues with the antenna) - took 20 minutes for him to understand me, literally. Finally asked another person that works there, Julio (who's been there for many years, done business with him personally in the past but I didn't expect him to remember me), and he understood right off what I was attempting to do. They didn't have a floor model or demo scanner ready to go and I wasn't trying to have them crack open a new box and use something (which would force them to legally then sell the item as used) so Julio suggested to the other guy to get a Yaesu dual bander HT that happened to be capable of CivAir airband tuning and it also had the required BNC/SMA adapter.

Got everything hooked up, powered up the receiver, tuned to 119.900 MHz AM (one of the main Tower frequencies for McCarran Airport which was about 1.5-2 miles away direct from the AES location) and after a minute or two we heard nothing at all which kinda disappointed me but, even in spite of it being Friday afternoon which is the busiest day for incoming traffic at McCarran - this is Las Vegas after all where the population of the town doubles and sometimes triples on the weekends - so I asked if the Yaesu could scan a range, he said he wasn't sure but knew it could do direct scanning (from the entered frequency either up or down) so I said scan up and he pushed the Up arrow or whatever and we watched the displayed frequency climb till it got to 123.825 MHz AM which is McCarran Helicopter Control and it was crystal clear, surprisingly loud for such a tiny HT unit actually, showing full bars on the signal strength meter as well.

Asked him to hit scan again and it stopped almost immediately at 124.400 MHz AM which is McCarran Ramp Control for a few of the gates, again loud and clear and typically something that would only be received from a short distance away from the airport. Perhaps my 6+ miles with terrain and a few buildings just hampers it so much the AL-500H can't hear stuff, I don't know - but I do occasionally get a hit on that frequency using the homebrew 1/4 wave ground plane I made which is cut for 150 MHz and it's inside as well.

Obviously the antenna does work and even given the proximity to McCarran (practically line of sight to the actual tower from where AES is located save for a casino or two in the way) I doubt that unit would pull a full strength signal like that without the AL-500H attached - it would probably get one without an antenna considering the distance but not that much of one.

I am baffled at how it's so deaf here at home using this RTL stick as compared to the other antennas I've been using but, it is what it is I suppose and I'll just make the best of it. Hoping to get a proper handheld soon, most likely a BC346XT, they had a demo model at a nice discount on the shelf but it'll have to wait a few weeks.

Anyway, that's the final result for the time being: the AL-500H apparently works, just not here at home worth a damn for some reason or with this "cheap USB TV tuner."

 

[davenlr]

Does the siding on your house have foil backed insulation on it?

 

[br0adband]

Not in a house, but in an apartment (3rd floor) with a huge window where all the other antennas are mounted when required, can't put anything outside or on the roof sadly which is only like 4 feet away.

Anyway, every other antenna gets a signal, even a paperclip in the BNC socket gets a stronger signal than the AL-500H does here at home using the current setup. I can even pull in 270.100 MHz AM (the Nellis AFB ATIS broadcast) using the Radio Shack 800 MHz duckie with signal levels that make it quite legible but if I disconnect that antenna and attach the AL-500H without moving or changing anything but the antenna itself I get dead air, no signal at all measured with either SDR# or SDR-Radio, like there's no antenna attached at all. The RH-C77A gets a legible signal, a random length of coat hanger gets a signal, a paperclip, a telescopic whip, etc, all pull in something at 270.100 MHz but the AL-500H gets nothing at all - same thing with the ATIS for McCarran at 132.400, and even the VOR for Boulder City Airport at 116.700. I'll see something on the spectrum with anything attached to the RTL stick but the AL-500H... well... I'm getting severely redundant now so I'm shutting up.

Bleh, you folks have heard enough about this - the testing at AES proved to me it works, I just don't know why it's so unbelievably "deaf" here attached to the same hardware that every other antenna finds a usable signal with.

It's just one of those things I guess. It's not like I can't receive stuff using the other antennas that work just fine, it's simply so odd and strange that this one that I bought specifically for it's intended design purpose happens to not do it with my setup.

 

[davenlr]

Only other thing I can think of is the pin on the antenna's center conductor is to short to contact the "center jack" on the scanners antenna jack, or is a smaller diameter and not making physical contact.

Can you pick up a NOAA channel with no antenna connected? If so, see what the signal level does when you plug in the antenna. It should make some difference (cut out or get stronger) I would think. If there isnt any difference, its almost got to be a bad connector on the antenna.

 

[br0adband]

Only other thing I can think of is the pin on the antenna's center conductor is to short to contact the "center jack" on the scanners antenna jack, or is a smaller diameter and not making physical contact.

Can you pick up a NOAA channel with no antenna connected? If so, see what the signal level does when you plug in the antenna. It should make some difference (cut out or get stronger) I would think. If there isnt any difference, its almost got to be a bad connector on the antenna.

Did you read this thread? It's all been covered multiple times because I'm a fairly redundant person including the fact that it was tested on a dual band HT earlier in the day and it worked exactly as expected, and even the aspect of the center pin potentially not making proper contact ("aluminum foil" was mentioned).

Anyway, don't worry about it since it's just one of those things... sometimes we get lucky, sometimes we don't.