papakb
Well-known member
- 2,288
- 1,185
- 113
- Location
- San Jose, Ca
This is a note to anyone that's experiencing problems with the SF-3512 antennas on what we've found. It's a great broadband antenna that's usable from 30 - 512 Mhz on newer military vehicles that bolts directly into most of the standard antenna brackets.
We've been experiencing issues with Shakespeares SF-3512 for about 3 years now since I worked on my first one and I have to say the company has been very supportive of my repair efforts over that time.
What happens with some of the earlire units is that the RG-316 coax that connects the N bulkhead connector to the BMA connector that connects to the antenna masts was too short and the shield would break in the crimp to the BMA connector if the antenna was pulled over too far for transit. Shakespeare corrected this and made the cable slightly longer.
I've worked on a couple more of these antenna bases and there's still a problem with the coax shielding breaking at the top BMA connector crimp. Opening up the new unit I found that they'd lengthened the cable, added RTV to the N connector crimp and added a rubber collar to minimize vibration in the mounting base but the coax shield crimp to the upper BMA connector was still breaking and we were losing continuity to the masts. Bad!
We're thinking the issue could be corrected by either adding another rubber collar to the upper coax crimp or RTVing the BMA connector into the collar that physically mounts it to the top of the spring where the masts attach. I've suggested this to Shakespeare and am waiting for a reply from them now.
I wanted to add a note to this post that I've found a source for the components to repair these bases so if you have one that isn't working feel free to contact me about them. The expensive part is the BMA connector on the top of the base that makes electrical connection to the mast. A complete replacement cable assembly runs about $75 ready to install.
We've been experiencing issues with Shakespeares SF-3512 for about 3 years now since I worked on my first one and I have to say the company has been very supportive of my repair efforts over that time.
What happens with some of the earlire units is that the RG-316 coax that connects the N bulkhead connector to the BMA connector that connects to the antenna masts was too short and the shield would break in the crimp to the BMA connector if the antenna was pulled over too far for transit. Shakespeare corrected this and made the cable slightly longer.
I've worked on a couple more of these antenna bases and there's still a problem with the coax shielding breaking at the top BMA connector crimp. Opening up the new unit I found that they'd lengthened the cable, added RTV to the N connector crimp and added a rubber collar to minimize vibration in the mounting base but the coax shield crimp to the upper BMA connector was still breaking and we were losing continuity to the masts. Bad!
We're thinking the issue could be corrected by either adding another rubber collar to the upper coax crimp or RTVing the BMA connector into the collar that physically mounts it to the top of the spring where the masts attach. I've suggested this to Shakespeare and am waiting for a reply from them now.
I wanted to add a note to this post that I've found a source for the components to repair these bases so if you have one that isn't working feel free to contact me about them. The expensive part is the BMA connector on the top of the base that makes electrical connection to the mast. A complete replacement cable assembly runs about $75 ready to install.
Last edited: