AS-1729/VRC with MX-6707 Base Matching unit for 10M 6M ham?

[RFI-EMI-GUY]

Has anyone any practical experience with this antenna on 10/6M ham operations? I see there are instructions to tune the 30 MHz coil to 29 MHz.

My application would be for FM operations with a 100 watt Motorola Syntor X9000 and remote band selection with a DEK style wildcard form C switch module and 12-24V converter.

1) General experiences with installation on an SUV like Ford Expedition?

2) VSWR to be expected on 10/6M and across the range (Part 90 at 35.04 and 43.04 MHz) ?

3) Power handling capability? The spec says 70 watts. Will 100 watts fry it?

4) Efficiency? Are they a workable solution?

Alternately I have been eyeing the AS-3900A/VRC and AS-3916A/VRC SINCGARS antennas which appear to compromise efficiency for simplicity and bandwidth. Same questions apply.

 

[prcguy]

I've used them on 6M and retuned one for CB. The antenna is center fed with a switched matching network as you know. At best a 1/4 wave tuned whip with adequate ground plane will outperform a 1729 on most frequencies and on its native resonant freq around 70MHz for the dipole it may work a little better. Its an ok option for military vehicle collectors who need maybe two or three frequencies like CB, 29MHz or 51.0MHz but I don't think its a good choice for general purpose amateur use on 10m through 6m.

The AS-3900 is worse and the AS-3916 is worse than a 3900, I've used them all. If you want to go big and green and you have a pickup truck or something that doesn't look completely ridiculous with one of these antennas, the Shakespeare SBF33512 series is not too bad, its close to a 1/4 wave resonant whip on most frequencies and you can diplex in your 2m and 70cm radios. I made provisions for one of those on my new truck. There are a few other companies that make similar 30-512MHz whips like Comrod sold through Harris.

 

[RFI-EMI-GUY]

Shakespeare SBF33512

Is that a good PN? Google not happy.

 

[prcguy]

SBF3512, oops.

Shakespeare SBF33512

Is that a good PN? Google not happy.

 

[prcguy]

Post #15 here has info on the Shakespeare SBF3512 and performance comparisons to a couple of scanner antennas.

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[RFI-EMI-GUY]

Thanks! Good write up.

With the Expedition I have the added problem of needing to mount the antenna at or just above the bumper which means the 6M radiation will be compromised. This may be a problem the alternative, a Hustler 48" mast plus 10M coil as a 6/10M solution. I assume the SBF3512 being end fed will perform likewise. My thoughts were that the AS-1729/VRC being center fed would radiate better. But then it is apparently less than a 1/4 wave at 6m.

Compromises abound with mobile HF and VHF low antennas.

 

[prcguy]

Hard to say if the non resonant dipole with elevated feed would work better than an end fed, both near the bumper. I put a military 4 hole mount on my new truck on the upper internal bed wall about 2/3 back from the cab and so far every antenna I've tested there works great with adequate ground plane and little blockage. Here is an actual Shakespeare SBF3512 on the new truck and I'll be testing that soon. The military mounts are big and ugly but if you can find a high spot to mount one you will open up a lot of new antenna options.

Thanks! Good write up.

With the Expedition I have the added problem of needing to mount the antenna at or just above the bumper which means the 6M radiation will be compromised. This may be a problem the alternative, a Hustler 48" mast plus 10M coil as a 6/10M solution. I assume the SBF3512 being end fed will perform likewise. My thoughts were that the AS-1729/VRC being center fed would radiate better. But then it is apparently less than a 1/4 wave at 6m.

Compromises abound with mobile HF and VHF low antennas.