Sirio HP4000 body mount?
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Sirio HP4000 body mount?
Hi,
I'm looking at body/panel mounting a Sirio HP4000 to a van roof and I'm struggling to find any suitable SO-239 mounts. The van roof is not flat, it has ridges so IIRC I have about 120mm in the centre of the roof to fit a mount. Fitting in the centre of the roof is a must not just for equal radiation pattern but for OCD reasons
I see Sirio have a panel mount available, but this is SO-239 for the antenna to a Sirio DV plug, I have tried but I can't find a power rating for this "DV plug" online but I know the DV27 antenna I last used this connector on (many years ago) only had a 100W rating, I would be looking to run a bit more than 100W hopefully.
I see lots of 3/8th to SO=239 mounts available but I want SO-239 on the roof and SO-239 or N type or anything that can handle a few hundred watts one the inside. I've always had RF feedback issue's when running power with mag mounts which is why I want to body mount.
I really don't want to ditch the HP4000 antenna as it's always been a great performer but why design a 1000W PEP antenna when there doesn't appear to be a 1000W PEP body mount available for it?
I'm looking at body/panel mounting a Sirio HP4000 to a van roof and I'm struggling to find any suitable SO-239 mounts. The van roof is not flat, it has ridges so IIRC I have about 120mm in the centre of the roof to fit a mount. Fitting in the centre of the roof is a must not just for equal radiation pattern but for OCD reasons
I see Sirio have a panel mount available, but this is SO-239 for the antenna to a Sirio DV plug, I have tried but I can't find a power rating for this "DV plug" online but I know the DV27 antenna I last used this connector on (many years ago) only had a 100W rating, I would be looking to run a bit more than 100W hopefully.
I see lots of 3/8th to SO=239 mounts available but I want SO-239 on the roof and SO-239 or N type or anything that can handle a few hundred watts one the inside. I've always had RF feedback issue's when running power with mag mounts which is why I want to body mount.
I really don't want to ditch the HP4000 antenna as it's always been a great performer but why design a 1000W PEP antenna when there doesn't appear to be a 1000W PEP body mount available for it?
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Re: Sirio HP4000 body mount?
I would guess that the most power you can run to an antenna depends on:
* the inner core thickness of the co-ax
* the melting point of the solder on all joints
* the coil windings of the aerial.
I should imagine it'll take a few hundred watts without getting too hot. An ultra-low SWR would be beneficial
I've got a so-called "heavy-duty" SO mount through the roof on my car (so it can withstand 70+mph against a tall aerial without deforming the metal roof) but 4 watts is all I'm ever likely to run through it!
* the inner core thickness of the co-ax
* the melting point of the solder on all joints
* the coil windings of the aerial.
I should imagine it'll take a few hundred watts without getting too hot. An ultra-low SWR would be beneficial
I've got a so-called "heavy-duty" SO mount through the roof on my car (so it can withstand 70+mph against a tall aerial without deforming the metal roof) but 4 watts is all I'm ever likely to run through it!
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Re: Sirio HP4000 body mount?
Thanks for the reply, just managed to find and order one of these which should be just the ticketThe Collector wrote: ↑19 Feb 2022, 10:56 I would guess that the most power you can run to an antenna depends on:
* the inner core thickness of the co-ax
* the melting point of the solder on all joints
* the coil windings of the aerial.
I should imagine it'll take a few hundred watts without getting too hot. An ultra-low SWR would be beneficial
I've got a so-called "heavy-duty" SO mount through the roof on my car (so it can withstand 70+mph against a tall aerial without deforming the metal roof) but 4 watts is all I'm ever likely to run through it!
https://moonrakeronline.com/rfs-s2-heav ... re=default
Is this what you are using?
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Re: Sirio HP4000 body mount?
Just watch with some of those beehive-type mounts. If they've got a large, triangular-shaped "washer" that grips the metal underneath the hole, the 3 slightly-angled points can slightly deform the metal at those points if the metal is thin and the washer is tightened too much.
Edit - just clicked on the other pic's. That one's got a multi-pointed grip washer design so it shouldn't deform the roof panel as easily.
I've got one like this on mine below.
A big, fat, top washer/ nut spreads the load. I used enamel paint on the drilled hole, allowed it to dry and then used a decent polyurethane body panel sealant around the hole before tightening the mount onto it. It should hopefully never leak. I think the description is wrong on the below, but the picture is of the mount I used:
https://www.ebay.co.uk/itm/CB-Antenna-A ... 635-2958-0
Edit - just clicked on the other pic's. That one's got a multi-pointed grip washer design so it shouldn't deform the roof panel as easily.
I've got one like this on mine below.
A big, fat, top washer/ nut spreads the load. I used enamel paint on the drilled hole, allowed it to dry and then used a decent polyurethane body panel sealant around the hole before tightening the mount onto it. It should hopefully never leak. I think the description is wrong on the below, but the picture is of the mount I used:
https://www.ebay.co.uk/itm/CB-Antenna-A ... 635-2958-0
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Re: Sirio HP4000 body mount?
I remember the DV27 mounts having the triangle shaped washer.... and what they did to the biscuit tin if you overtightened , good shout.
It's going onto a 6 year old works van that's a bit beat up already so I'm not too concerned about the roof as long as if worst came to worst I could fit a grommet and seal it up water tight again. The van will be driven until it's dead so no need to worry about resale value.
I did think of fitting some sheet steel/ali on the underside of the roof to spread the load out a little but the reviews on the mount I bought complain of the threads not being long enough if the roof is a little on the thick side, so looks like I'll have to fit it and hope for the best.
What's the worst that could happen? I turn the van into a pickup?
It's going onto a 6 year old works van that's a bit beat up already so I'm not too concerned about the roof as long as if worst came to worst I could fit a grommet and seal it up water tight again. The van will be driven until it's dead so no need to worry about resale value.
I did think of fitting some sheet steel/ali on the underside of the roof to spread the load out a little but the reviews on the mount I bought complain of the threads not being long enough if the roof is a little on the thick side, so looks like I'll have to fit it and hope for the best.
What's the worst that could happen? I turn the van into a pickup?
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Re: Sirio HP4000 body mount?
...or it leaks and you have a mobile aquarium
1-9 for a carp-y lol.
If you can push the roof panel and it flexes, then another layer of metal would be a good idea if you're going to use a Firestik or something substantial, but for a base-loaded aerial you should be okay.
Saying that, if you whack any low branches near to the coil, then the panel could possibly kink a little.
Even an extra millimetre of thickness would help, say about 8 inches wide, but if you can't, you can't.
1-9 for a carp-y lol.
If you can push the roof panel and it flexes, then another layer of metal would be a good idea if you're going to use a Firestik or something substantial, but for a base-loaded aerial you should be okay.
Saying that, if you whack any low branches near to the coil, then the panel could possibly kink a little.
Even an extra millimetre of thickness would help, say about 8 inches wide, but if you can't, you can't.
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Re: Sirio HP4000 body mount?
Any updates on this at all?26OD004 wrote: ↑21 Feb 2022, 22:01 I remember the DV27 mounts having the triangle shaped washer.... and what they did to the biscuit tin if you overtightened , good shout.
It's going onto a 6 year old works van that's a bit beat up already so I'm not too concerned about the roof as long as if worst came to worst I could fit a grommet and seal it up water tight again. The van will be driven until it's dead so no need to worry about resale value.
I did think of fitting some sheet steel/ali on the underside of the roof to spread the load out a little but the reviews on the mount I bought complain of the threads not being long enough if the roof is a little on the thick side, so looks like I'll have to fit it and hope for the best.
What's the worst that could happen? I turn the van into a pickup?
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Re: Sirio HP4000 body mount?
Yes, but not what you would expectThe Collector wrote: ↑19 Mar 2022, 19:25Any updates on this at all?26OD004 wrote: ↑21 Feb 2022, 22:01 I remember the DV27 mounts having the triangle shaped washer.... and what they did to the biscuit tin if you overtightened , good shout.
It's going onto a 6 year old works van that's a bit beat up already so I'm not too concerned about the roof as long as if worst came to worst I could fit a grommet and seal it up water tight again. The van will be driven until it's dead so no need to worry about resale value.
I did think of fitting some sheet steel/ali on the underside of the roof to spread the load out a little but the reviews on the mount I bought complain of the threads not being long enough if the roof is a little on the thick side, so looks like I'll have to fit it and hope for the best.
What's the worst that could happen? I turn the van into a pickup?
Injector went on the van, so had all 4 replaced. Since then it's been losing coolant, been back in and tested the coolant which shows evidence of exhaust gasses absorbed into the coolant. They think there is a crack in the head or head gasket has gone. Either way, new engine or new van required
Just waiting for the powers that be to decide what they want to do with it, so I've held off installing anything for now...
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Re: Sirio HP4000 body mount?
Ahhh... yes...I see
Not worth bothering with until you know what's what.
I've got myself a Sirio Megawatt 4000 now, big buggers these 4000's aren't they I really wanted a 5000 "Rigid" but can't get one over here.
Not worth bothering with until you know what's what.
I've got myself a Sirio Megawatt 4000 now, big buggers these 4000's aren't they I really wanted a 5000 "Rigid" but can't get one over here.
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Re: Sirio HP4000 body mount?
I have tried a fair few mobile antennas over the years, modulators, dv's, sirio ml-145, firesticks etc. The 4000 is the best performing antenna that I've tried that I'm comfortable to drive around with. I did compare it to a 9 foot tank whip (while stationary obviously) and the whip just edged it, but not by much. IIRC when I changed from the ML-145 to the 4000 There was at least 1-2 s point improvement. It also would take all the power a KL500 could throw at it with no ill effects, but yes, they are rather tall
Used to make my little vauxhall astra look like a dodgem
Used to make my little vauxhall astra look like a dodgem
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Re: Sirio HP4000 body mount?
That's the main problem with big aerials, it's aesthetics vs performance. A 3 or 4ft twig looks good, but to get out well, you really need over 5ft. But, then you get a swinging/pendulum action whilst mobile, especially around town, the received signal bouncing around from s2 - s7 etc. Static-mobile's a different matter of course.
I used to run around in my Escort mk1 with a Tagra t40 on a boot mount which was 5ft (very similar to a K40 but with a tapered whip which helped against the whip swinging so badly), or a centre-loaded Modulator on a 6" magmount on the roof and even a 2ft dial-a-match which I could attach to the gutter-mount on my Cavalier mk2 through the window whilst driving
Although I no longer use CB, I have a PNI165 aerial (like ml145 but 200mm bigger, was only £12 delivered) and now the MW4000 should I ever need to go mobile. I doubt I ever will but the MW was in amongst a job-lot of stuff I recently bought.
I used to run around in my Escort mk1 with a Tagra t40 on a boot mount which was 5ft (very similar to a K40 but with a tapered whip which helped against the whip swinging so badly), or a centre-loaded Modulator on a 6" magmount on the roof and even a 2ft dial-a-match which I could attach to the gutter-mount on my Cavalier mk2 through the window whilst driving
Although I no longer use CB, I have a PNI165 aerial (like ml145 but 200mm bigger, was only £12 delivered) and now the MW4000 should I ever need to go mobile. I doubt I ever will but the MW was in amongst a job-lot of stuff I recently bought.