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whiteastro
08-24-2019, 06:42 PM
Well after months of waiting and reading up on this New SPT 500 antenna I finally finished it up today with results I can live with. I hope this helps someone else who wants to set it up for 11 meter. I first started out with setting it at 22' 6" and had acceptable SWR but wanted to get a better reading so I raised and lowered it multiple times until it was at 22' 8" with a 1-1.5 SWR on channel 1 and a 1-.5 on channel 40. Even though my raising and lowering was easy because of my custom built pivot mount I built and using a winch on my tractor I started to tire of playing around so the last time I changed it to 22' 9" and got a reading of 1-1.1 on channel 1 and a reading of 1-1.1 on channel 40, and a flat line reading on channels 17 19 and 20 the channels I use most. Good enough for me. Now I can't wait for the DX to start rolling in. Hope this helps somebody because their is too much mixed info on this antenna.

Cheers:untroubled:

nosaj
08-25-2019, 10:52 AM
Well part of the problems lie in the installation. How high, what is near it, metal roofs can affect swr, soil conductivity. A myriad host of issues that prevent most antennas installs from being a simple put it up and talk.
So in effect each antenna installation can be as individual as each of us.

nosaj

whiteastro
08-25-2019, 12:15 PM
Well part of the problems lie in the installation. How high, what is near it, metal roofs can affect swr, soil conductivity. A myriad host of issues that prevent most antennas installs from being a simple put it up and talk.
So in effect each antenna installation can be as individual as each of us.

nosaj

What your saying is so true that is why I found so many differences of opinion and why I jumped a full 1" on my last adjustment because I read somewhere that 22' 9.5" was the magic number. I was at 22" 8" and I figured 22" 9" would still leave me room to play. I have to laugh because it is a tough game for a OLD FART like me to play! LOL:israel:

nosaj
08-25-2019, 01:02 PM
Yea if it's on the internet it must be true! :0
I've only been in this a year but come from an audio background in tube amps and the antenna to me is like the speaker load if not right it'll burn up your amp.
It's a shame more people don't try to understand some of what they use.
nosaj

whiteastro
08-25-2019, 01:15 PM
Yea if it's on the internet it must be true! :0
I've only been in this a year but come from an audio background in tube amps and the antenna to me is like the speaker load if not right it'll burn up your amp.
It's a shame more people don't try to understand some of what they use.
nosaj

I've been a poor boy a long time, can't afford to burn up my radios. Too many places to spend money so I pay attention to detail. LOL

nosaj
08-25-2019, 01:25 PM
Same here, got more skills than money through being poor, I've also gotten to play with whatever toys I want by buying broken. Did that the entire time kids were growing up. They wanted a game system buy a broken one cheap and fix it. They rarely ever got anything brand new but I did what I could and they now do the same.
It's amazing what people get rid of....an we just scoop up.

nosaj

whiteastro
08-25-2019, 02:56 PM
That's me an old scooper. LOL I'm scooping up all the good knowledge these good people will share with me. LOL

Danr
05-14-2020, 05:25 PM
Did you have to do any thing to your radials such as shorten them ?

whiteastro
05-14-2020, 05:56 PM
Did you have to do any thing to your radials such as shorten them ?

No I didn't shorten them, I set them per the instructions and things worked out fine. Setting the height for 11 meter is the important thing and every bodies install can be a little different. But for starters I believe you could start at 22' 9.5" and adjust from there. I've been playing with mine for a year and mine is set at 22' 9" and I think I could shorten it by maybe a 1/4- 1/2" but the SWR is good so it probably won't get done.

Big Moe
10-02-2020, 07:23 PM
This is really interesting...I just posted a pic of my antenna looking to identify it and looking for instructions and wouldn't you know it...I have a Hy-Gain SPT 500 Penetrator lol. Well....looks like my questions were answered. Now to get it tuned when the weather cools of a bit more here in Az.

whiteastro
10-03-2020, 04:44 AM
This is really interesting...I just posted a pic of my antenna looking to identify it and looking for instructions and wouldn't you know it...I have a Hy-Gain SPT 500 Penetrator lol. Well....looks like my questions were answered. Now to get it tuned when the weather cools of a bit more here in Az.


Your welcome and I'm happy this thread answered your questions. That is what this forum is about, helping each other out. So many in here has helped me so it is good to pass it on. Looking at your picture post I see you have the older style original antenna with the wire style element at the base. The new ones have changed to flat sheet metal instead of wire style. But they are suppose to be electrically the same. Good luck and happy DXing!

Big Moe
10-03-2020, 02:34 PM
Believe me I was happy to see your info. I was about to order a new antenna. I found the installation instructions so now I have the exact measurements to tune this in correctly. I put it up and messed with it for about a week trying to get it tuned then gave up, that was about a year ago. Thanks again!

whiteastro
10-03-2020, 04:26 PM
Believe me I was happy to see your info. I was about to order a new antenna. I found the installation instructions so now I have the exact measurements to tune this in correctly. I put it up and messed with it for about a week trying to get it tuned then gave up, that was about a year ago. Thanks again!


The top section of the whip is all you move up and down to adjust the swr and if you take your time and be picky it should give you a great swr reading across the 11 meter band. But like they say it can vary just a little because of your situation, and make sure you seal off your coax connection because it it exposed to the elements. I put heat shrink tube on mine. Good luck and let me know what your SWR ends up!

Big Moe
10-03-2020, 04:38 PM
I'll get back to it in a couple of weeks but I'll let ya know!

BOOTY MONSTER
10-05-2020, 07:58 PM
keep in mind that when you mount a antenna on a metal mast/tower and/or add a wire to earth ground it does effect the tuning of the antenna but typically it's very little to trivial . if you want to split hairs adjusting ground elements can help you achieve that goal . IMO if you've got an acceptable VSWR it isn't worth the effort , but to each their own .

whiteastro
10-06-2020, 04:16 AM
keep in mind that when you mount a antenna on a metal mast/tower and/or add a wire to earth ground it does effect the tuning of the antenna but typically it's very little to trivial . if you want to split hairs adjusting ground elements can help you achieve that goal . IMO if you've got an acceptable VSWR it isn't worth the effort , but to each their own .


While I have no official radio training I turn to technical data to make my system be all it can be to make up for all the shortcomings I can't control. But like you said, To each their own! http://www.firestik.com/Tech_Docs/SWRLOSS.htm

BOOTY MONSTER
10-06-2020, 08:38 PM
do keep in mind when using loss charts that even a doubling or halving of power doesn't make much difference in making or not making a dx contact . but i do appreciate you using "technical data to make my system be all it can be to make up for all the shortcomings I can't control " . a more real issue/danger (IMO) is damaging equipment with a vswr beyond what it can survive .

whiteastro
10-07-2020, 06:34 PM
Of coarse avoiding damage to your radio is priority #1 in setting SWR, but geographic area is also a concern for some of us due to limitations it puts on us running barefoot in a mountainous area. I checked out Richmond VA info and it looks like you have low rolling hills with a elevation of less than 200' above sea level so it looks like your more fortunate when it comes to radio communications. Around here we have extreme sudden changes in elevation almost like riding a huge rolley coaster and doing it barefoot is a pain in the back side. If your getting in the DX game you just turn on the foot warmer to help you out. Myself I'm starting to tire of the extra noise when skip isn't rolling so the warmer is staying off most of the time. Thanks for the input and thoughts and like always Happy DXing!

Big Moe
10-07-2020, 07:02 PM
I have the antenna down and took the mast apart for proper measurements. The instructions show the exposed length of each mast pipe. My dilemma is, the mast pipe that slips into the base mast is not long enough to have 52 1/8" exposed per instructions. It's 52 1/4" long. Can the difference be made up in the top section??

Big Moe
10-07-2020, 07:08 PM
Just an FYI...I've been around CB's for better than 40 years. I appreciate tips and tricks to getting things done as I may have forgotten a few things over time :grin:.

BOOTY MONSTER
10-07-2020, 09:13 PM
i'm in tazewell va in the blueridge mountians on top of a ridge line , no longer in richmond . but you are absolutely correct that location/terrain plays a big role in how our systems perform . i don't have my stuff set up , been doing a lot of fixing up around here .

whiteastro
10-08-2020, 04:32 AM
I have the antenna down and took the mast apart for proper measurements. The instructions show the exposed length of each mast pipe. My dilemma is, the mast pipe that slips into the base mast is not long enough to have 52 1/8" exposed per instructions. It's 52 1/4" long. Can the difference be made up in the top section??


How old is you antenna system, is it one of the originals? You should be able to make your final adjustment with the top section of mass. My instructions say overlap each section of mass 2-3" instead of a set measurement. If your antenna was put together for a long period of time they should be discolored where they were joined together, I would slide them back the way they were on a set of saw horses on the ground and see if they end up with your final measurement. My instructions say a final measurement of 22' 6" but it was marketed for 10/12 Meter not the 11 meter band. If yours is a original it should say 22' 9.5" for 11 meter. 2-3" of overlap of each section allows a wide variance in end product before you clamp it together. Good Luck don't sweat the small stuff and let us know the end result! PS It's human nature to forget over time, I forgot if I set my overlap at 2" or 3" LOL

whiteastro
10-08-2020, 04:38 AM
i'm in tazewell va in the blueridge mountians on top of a ridge line , no longer in richmond . but you are absolutely correct that location/terrain plays a big role in how our systems perform . i don't have my stuff set up , been doing a lot of fixing up around here .


I can appreciate that because I have been nothing but a slave to my house this summer!

Big Moe
10-08-2020, 06:46 AM
I believe it's an original. The first instructions I downloaded shows measurements for each pipe. I went back and found another set of instructions and it shows the 2-3" of overlap. I'll set it with the overlap and get an overall length like you have, 22' 9" and see what the swr is at.

whiteastro
10-08-2020, 04:58 PM
I believe it's an original. The first instructions I downloaded shows measurements for each pipe. I went back and found another set of instructions and it shows the 2-3" of overlap. I'll set it with the overlap and get an overall length like you have, 22' 9" and see what the swr is at.


Good luck! I always thought I might have been able to shorten it another 1/4-1/2" but 22' 9" gave me a great SWR and by that time I was tired of raising & lowering so I said good enough. Like Booty Monster said, I would have been Splitting Hairs. LOL

BOOTY MONSTER
10-08-2020, 08:09 PM
kinda off topic ...... but this is one reason i like the maco tapped ring type tuning method . much easier to tune .

Big Moe
10-08-2020, 09:49 PM
22'9" gave me a bit of a high swr. 1.5 on channel 1 and 1.8 on 40 so now begins the fun.

whiteastro
10-09-2020, 04:18 AM
22'9" gave me a bit of a high swr. 1.5 on channel 1 and 1.8 on 40 so now begins the fun.


Make sure your coax connections are clean with a little Di-electric grease, and shorten your antenna a half inch. Good luck PS with using a older antenna make sure you don't have a corrosion problem at any connection mechanical or electrical, including the coax itself.

whiteastro
10-09-2020, 04:20 AM
kinda off topic ...... but this is one reason i like the maco tapped ring type tuning method . much easier to tune .


The maco V or W 58 antenna looks and sounds interesting!

BOOTY MONSTER
10-09-2020, 08:03 PM
well , pick your poison if you're gonna leave it stock . they don't have the length to actually be a 5/8 wavelength on the cb band . of course you can add a length of aluminum tube to make it a true 5/8 or .64 WL and there should be plenty of adjustment on the tapped ring for the extra length . i home brewed one years ago and it tuned just fine . those parts are now used on my home brewed sigma 4 /vector 4000 . if you already have the hygain it is a more durable antenna with beefier components and i would stick with it . it should be worth the extra effort to tune it .

a very nice thing about both of these antennas is that they don't have any hidden solder connections in the matching network so you don't have to worry about buying another antenna if/when it fails . just clean any corrosion off (if it develops) and stick it back up . however ..... sometimes moisture (rain/snow) can effect the tuning a point or two but if it's tuned adequately it shouldn't be a problem , unless you're a needle watcher .

whiteastro
10-10-2020, 04:25 AM
well , pick your poison if you're gonna leave it stock . they don't have the length to actually be a 5/8 wavelength on the cb band . of course you can add a length of aluminum tube to make it a true 5/8 or .64 WL and there should be plenty of adjustment on the tapped ring for the extra length . i home brewed one years ago and it tuned just fine . those parts are now used on my home brewed sigma 4 /vector 4000 . if you already have the hygain it is a more durable antenna with beefier components and i would stick with it . it should be worth the extra effort to tune it .

a very nice thing about both of these antennas is that they don't have any hidden solder connections in the matching network so you don't have to worry about buying another antenna if/when it fails . just clean any corrosion off (if it develops) and stick it back up . however ..... sometimes moisture (rain/snow) can effect the tuning a point or two but if it's tuned adequately it shouldn't be a problem , unless you're a needle watcher .


For sure there is no perfect antenna and I'm done buying antennas. People tend to brag about what they have and not tell you the down side of it. I actually took my Super Penetrator down and have settled on just my Sirio Starduster because the SWR stays consistent in all weather. The Penetrator changed SWR considerably in the rain and turning on the amp compounded the problem. I have no time to baby sit a antenna because too many other things in life going on, and the Star Duster works in this valley. I have read in other posts people have found ways to eliminate the rain problem with the Penetrator but I have no time for that because of finishing work on my house. If I ever get out of here I might try a Beam antenna but for now my Sirio Star Duster serves me good enough and I have laid the Hype to rest. The only reason I mentioned the Maco V58 was because my locale CB shop has one set up and he says it isn't affected by rain, snow, or ice.

BOOTY MONSTER
10-13-2020, 07:25 PM
location is everything . down in a hole/valley the higher take off angle of the 1/4 wave GP would be beneficial .

whiteastro
10-14-2020, 05:21 AM
location is everything . down in a hole/valley the higher take off angle of the 1/4 wave GP would be beneficial .


Thank BM I read that in one of your other post and it helped confirm what my old Ham buddy Dray also told me. Don't get me wrong I wish I had more time to build my own antenna, but I have to be practical. You guys that are into radio have helped me a lot and sure enjoy learning from these forums! PS I'm sure the Penetrator in the right spot would be a great antenna if you took time to fix the Hic-cup with the rain problem.

whiteastro
10-14-2020, 05:41 AM
My first antenna when I got back into CB was a Workman M400 Starduster because it was affordable and it ran great for years with a low SWR until water got in it and it froze and split. That was because they didn't drill a weep hole in the bottom of it like Sirio does in theirs. I have fixed that old workman antenna and put a weep hole in it so it is ready to ride again for someone.

Big Moe
10-14-2020, 11:53 AM
I'm done with this old antenna and trying to tune it. Thanks to those who had some tips and tricks on these but I'm done messing with it. Time to buy a new antenna that I know works and new coax so everything is fresh. I'v had an Antron 99 before and it worked great plus tuned super simple.

whiteastro
10-14-2020, 06:00 PM
I'm done with this old antenna and trying to tune it. Thanks to those who had some tips and tricks on these but I'm done messing with it. Time to buy a new antenna that I know works and new coax so everything is fresh. I'v had an Antron 99 before and it worked great plus tuned super simple.


Sorry it didn't work out for you but if you read the other posts in here the penetrator is bothered by rain so I took mine down. What ever antenna you put up make sure it is not bothered by rain, ice, or snow and high wind. That way you can enjoy your investment when ever you want. Good Luck!

Big Moe
10-14-2020, 06:19 PM
I ordered another Antron99. Here in this part of Az it never snows and hardly rains so I'm good lol.

Buzzweiser
10-20-2020, 01:52 AM
I bought one of the new SPT-500's about 5 years ago to replace my Proton-99. I opened the box, looked at it, closed the box and sold it on Craigslist 2 days later. Ended up 2 days later with an IMax.

frontshadow
11-14-2020, 06:58 PM
....replacing my old Maco 5/8 with a SPT500....hoping it does equally as well.

whiteastro
11-15-2020, 06:41 AM
....replacing my old Maco 5/8 with a SPT500....hoping it does equally as well.


The SPT500 gets a lot of good reviews but what they don't tell you is it is bothered by rain and snow&ice. If you don't have it already I would consider the Maco V58 as it is not bothered by rain,snow& ice. If you have the SPT 500 already search for the post on weather proofing it. I've seen it posted on the net but can't remember where or I would send you a link to it. The SWR gos bad in the rain on the SPT 500 but returns to normal after it stops raining. That is why I took my SPT 500 down and settled for my Staduster which isn't bothered by the elements. Good Luck

frontshadow
12-02-2020, 05:00 PM
I've had nothing but SWR troubles with the Maco ever since I've had it new as original owner. Several times I've reset the SWR, carefully marked the radials (which have never moved). Weather seems to affect it easily. Heavy rains drive the background up 1-2 S Units. It works great as long as the weather stays fairly constant. I've changed radios, coax, used No Ox, greased and waterproofed connections, and the problem still comes and goes with weather. I have two other ground planes and a beam. They all are consistent. Maco even sent me a new 5/8 as I complained so much. So, I'm trying the Penetrator.

whiteastro
12-02-2020, 05:31 PM
I've had nothing but SWR troubles with the Maco ever since I've had it new as original owner. Several times I've reset the SWR, carefully marked the radials (which have never moved). Weather seems to affect it easily. Heavy rains drive the background up 1-2 S Units. It works great as long as the weather stays fairly constant. I've changed radios, coax, used No Ox, greased and waterproofed connections, and the problem still comes and goes with weather. I have two other ground planes and a beam. They all are consistent. Maco even sent me a new 5/8 as I complained so much. So, I'm trying the Penetrator.


Which Maco antenna are you talking about having trouble with in the rain. I was referring to the Maco V58 which I had 2 other operators tell me from their experience that their V58 was not bothered by the elements. I know from my experience and 2 other posts that 3 operators had rain problems with the SPT 500 Penetrator. Let me know how you make out because trying antennas gets expensive. I do know from my experience of probably around 15 years I never had a problem with my Lowly old StarDuster antenna so I would be satisfied with just keep using it. Good Luck and hope it works out for you !

Cedar Mountain Radio
01-05-2021, 01:31 AM
Reading this thread I had to go dig out my old 1970s Penetrator and ask myself what it is about that design that doesn't like water - and the only thing I can imagine might have something to do with the flat plastic insulators which hold the hairpin match in place.

They're flat and I suppose could catch and hold a lot of dust and dirt blowing around during the dry months so that when the rain comes it might be mixing with the minerals which have settled on the flat plastic, making a semi-conductive "mud".

I wonder if drilling them out so there is a lot less area to catch both dirt and water if it might not help to mitigate it's out of tune condition in the rain?

I recall some 20+ years ago when it was up that I did notice a little rise in swr but I don't recall it being more than maybe a 1.3:1. I wonder if the old original first gen Penetrator has a lesser tendency to go out of tune in the rain compared with the new SPT-500?

Maybe spray-insulating the main radiating element with Flexseal or Plastidip around those insulators and where it goes down through the radial hub might also help prevent high swr rain detuning?

Maybe I'll polish it up and throw it up there in place of the I10k and try a few things, now that it's rain season.

whiteastro
01-05-2021, 05:57 AM
Reading this thread I had to go dig out my old 1970s Penetrator and ask myself what it is about that design that doesn't like water - and the only thing I can imagine might have something to do with the flat plastic insulators which hold the hairpin match in place.

They're flat and I suppose could catch and hold a lot of dust and dirt blowing around during the dry months so that when the rain comes it might be mixing with the minerals which have settled on the flat plastic, making a semi-conductive "mud".

I wonder if drilling them out so there is a lot less area to catch both dirt and water if it might not help to mitigate it's out of tune condition in the rain?

I recall some 20+ years ago when it was up that I did notice a little rise in swr but I don't recall it being more than maybe a 1.3:1. I wonder if the old original first gen Penetrator has a lesser tendency to go out of tune in the rain compared with the new SPT-500?

Maybe spray-insulating the main radiating element with Flexseal or Plastidip around those insulators and where it goes down through the radial hub might also help prevent high swr rain detuning?

Maybe I'll polish it up and throw it up there in place of the I10k and try a few things, now that it's rain season.


Thanks for your thoughts and please let me know how you make out. This company now owns the Hygain name https://mfjenterprises.com/ and if you look in there you can find a phone # for support which I plan on doing when I get time to see if they have a solution to the problem. I see somewhere on the internet where someone found a remedy but I didn't bookmark it. ( Dummy Me ) I have to look around in the many forums I belong to to find the post. Before you start modifying and can't reverse your action do some checking first. It is a great antenna and someone has found a solution but I have so much on my plate I just haven't had time to devote to it yet. If I find it I will let you know because you took the time to be concerned and that is a good thing. Radio people seem to be a good bunch of helpful people and make the hobby enjoyable !

Cedar Mountain Radio
01-12-2021, 09:48 AM
Please post the "cure" if you end up coming across it@!

whiteastro
01-12-2021, 05:46 PM
Please post the "cure" if you end up coming across it@!


Will do on the cure to help a bunch of good guys. Nothing like giving !

deriter
02-27-2021, 07:49 PM
I just found an old Hygain Super Penetrator antenna the other day. I plan to rework it and get it put to use. Back in the 70's I had the golden super penetrator. I do remember the swr going up a little but not dramatically. I also had a starduster antenna and it was not affected by rain.
CMR mentioned maybe it was the plastic between the hairpin matching device and the bottom of the radiator and the rain causing a short. What if the hairpin was insulated itself? So that the rain could not make the short between the pin and the radiator. And then again, maybe it would still make the short down at the bolt connection.
I too would like to hear the solution.

whiteastro
02-27-2021, 08:14 PM
I just found an old Hygain Super Penetrator antenna the other day. I plan to rework it and get it put to use. Back in the 70's I had the golden super penetrator. I do remember the swr going up a little but not dramatically. I also had a starduster antenna and it was not affected by rain.
CMR mentioned maybe it was the plastic between the hairpin matching device and the bottom of the radiator and the rain causing a short. What if the hairpin was insulated itself? So that the rain could not make the short between the pin and the radiator. And then again, maybe it would still make the short down at the bolt connection.
I too would like to hear the solution.


Ok I have been checking on that problem and asking questions in worldwide dx forum and this is what they are telling me but I haven't had a chance to try it yet. They say on the matching device on the bottom there is 2 plastic insulators and the top one should have the long end of the insulator pointing up instead of down like mine came. So i guess I have to switch it around. One guy in that forum made his own top insulator out of better material and claims it solved the problem. Go to that forum and check it out because there is a lot of pics. Myself I'm going to switch my insulator first and give it a try after I talk with HyGain technical support. Good luck and keep us posted because it will help many with this common problem ! https://www.worldwidedx.com/register/register

deriter
02-27-2021, 09:44 PM
Thank you whiteastro. Without seeing the pictures, I assume by repositioning the plastic insulator, it causes the rain to shed? I was unable to view the site you posted, but when I receive the replacement parts that I will order I will make sure to look carefully at the parts to make sure as to how they are installed. Thanks again!

whiteastro
02-28-2021, 06:59 AM
Thank you whiteastro. Without seeing the pictures, I assume by repositioning the plastic insulator, it causes the rain to shed? I was unable to view the site you posted, but when I receive the replacement parts that I will order I will make sure to look carefully at the parts to make sure as to how they are installed. Thanks again!


I have to ask. Did you join that site so you could ( Log In ) You might not be able search and find the pictures unless you log in. If you can log in to that site I will send a link here so you can go to that page and log in. It's in the CB Antenna section. https://www.worldwidedx.com/threads/cb-base-station-antenna-question.220147/page-2#post-756214 (https://www.worldwidedx.com/threads/cb-base-station-antenna-question.220147/page-2#post-756214)

whiteastro
02-28-2021, 07:14 AM
A lot of members here belong to several forums for collective Ideas & Thoughts. Like they say 2 Heads are better than 1

deriter
02-28-2021, 12:49 PM
No I did not join that site. I will look into that.
I did see a post on here that said the base replacement was $50. I sure don't want to put that much into this antenna. Makes me think I should have went with something else. But this is what I have, so I guess I will have to keep moving forward. It is an old one, has the three section radials and I believe two bolts on the radial clamp. One of the top hat radials broke off at some point in time. And of course the two plastic spacers are gone and figured I would just go ahead and replace the plastic in the radial clamps. But its that base that I am concerned with. I asked about just replacing the plastic bottom that holds coax connector and they said something about a wire inside.
Guess I will have the satisfaction or frustration of rebuilding the old thing.

whiteastro
02-28-2021, 04:44 PM
No I did not join that site. I will look into that.
I did see a post on here that said the base replacement was $50. I sure don't want to put that much into this antenna. Makes me think I should have went with something else. But this is what I have, so I guess I will have to keep moving forward. It is an old one, has the three section radials and I believe two bolts on the radial clamp. One of the top hat radials broke off at some point in time. And of course the two plastic spacers are gone and figured I would just go ahead and replace the plastic in the radial clamps. But its that base that I am concerned with. I asked about just replacing the plastic bottom that holds coax connector and they said something about a wire inside.
Guess I will have the satisfaction or frustration of rebuilding the old thing.


Just keep in mind that you can spend a lot of time and money refurbishing a old antenna with all the little hidden cost of parts and supplies. Cleaning all the old corrosion on aluminum is a must for it to work proper. But some guys like the satisfaction of a do-it yourself project and don't count their time. Here is where you can buy a new one for comparison. https://www.dxengineering.com/parts/hgn-spt-500 There might be better or cheaper antennas if you look around, just remember if you ask some every antenna they have is the best going. Have fun and Good luck!

Cedar Mountain Radio
05-17-2021, 09:25 AM
I can't imagine that turning a piece of plastic upside-down would make any significant difference. Who was it that told you that (like I have to ask - lol)
I'll try Flexseal. I'm going to spray it all over the base once I get it tuned - and maybe that will seal out any water ingress causing high swr.

Also, the old original penetrators had the top hat rods bent down at a 45° angle so they didn't act like a capacity hat and make the antenna electrically too long. I've owned 3 brand new from the mid - late '70s and they all came out of the box with the radials already bent down at a 45° angle.

I don't believe they're necessary, there have been far too many great working antennas on the market over the years with nothing on top for me to think that the top hat is anything more than just for looks.

I'm going to put mine back up with a straight top about 8"- 9" longer and without the top hat. I'll probably have to cut off the top 1" threaded piece and add a foot long or so piece of tubing into the top to get the extra 8"- 9".

I seem to recall that I did that years ago with someone else's Penetrator and it worked perfect and measured 22' 3" from the 8' 8" radials to the tip for 27.300

BigMoe, it sounds like you were within 3"- 4" of needed shortening in order to get a flat swr, why give up?

whiteastro
05-17-2021, 05:49 PM
I can't imagine that turning a piece of plastic upside-down would make any significant difference. Who was it that told you that (like I have to ask - lol)
I'll try Flexseal. I'm going to spray it all over the base once I get it tuned - and maybe that will seal out any water ingress causing high swr.

Also, the old original penetrators had the top hat rods bent down at a 45° angle so they didn't act like a capacity hat and make the antenna electrically too long. I've owned 3 brand new from the mid - late '70s and they all came out of the box with the radials already bent down at a 45° angle.

I don't believe they're necessary, there have been far too many great working antennas on the market over the years with nothing on top for me to think that the top hat is anything more than just for looks.

I'm going to put mine back up with a straight top about 8"- 9" longer and without the top hat. I'll probably have to cut off the top 1" threaded piece and add a foot long or so piece of tubing into the top to get the extra 8"- 9".

I seem to recall that I did that years ago with someone else's Penetrator and it worked perfect and measured 22' 3" from the 8' 8" radials to the tip for 27.300

BigMoe, it sounds like you were within 3"- 4" of needed shortening in order to get a flat swr, why give up?

If you look at the top plastic insulator on the new one the bottom of the insulator is actually longer so if it was switched over it would be longer on the top and would shed water better instead of puddling water at the matching device. I'm actually working on a extension to the present insulator made from a PVC fitting which should do the same thing without taking the whole matching device apart and should be a simple fix. I'm getting ready to put the antenna back up and test it. If it works I'll post the pictures. To each their own but I won't do any modifications that can't be easily undone because I have too much invested to scrap a antenna. LOL

whiteastro
06-10-2021, 05:37 AM
Final testing of insulator mod. Tested in pouring down rain and no more SWR problem. Making is what the insulator is made from. Insulator is on the R/H and made from is on the L/H. Finish is the insulator sealed in place with out taking the whole matching device apart.
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