Batboard

Hi All,

I am new to this forum and have a question regarding portable repeaters. Has anyone had any experience in setting up a portable repeater? The intention would be to use 2x HTs like Visar, P100, P200 etc setup as a low power repeater that could be transportable and setup quickly. The main premise is low power consumption of the system as it would likely be remote -(high output power on the repeater is not so important). I have some ideas here regarding the design but want to get some feedback from anyone with experience. I have seen the pages on Batlabs re the Handie-Talkie RF link and figure what I need to design is something similar. There doesnt seem to be much information on this device due to the age I think.
Thanks for looking and any suggestions you might be able to offer would be much appreciated.

problem wouldnt be with the interface,itd be about duplexers, and desense

simonm

Did you ever get anywhere with it ???

I am looking to do the same thing, and was wondering if you got yours to work or not ???

Setting up a Portable Repeater Package is nothing new as they have been around for years. I would probably use the HT600 / P200 as the basic Transmitter and Receiver for an Analog version repeater. If you wanted something that could do Astro then I'd use Astro System Sabers.

The key to building such a package, requires a great deal of attention paid to the Shielding and DC Filtering for the Handheld Portables. Especially the Duplexers Frequency separation on VHF of 1.6 MHz Tx to Rx Minimum. On UHF the Frequency separation should be 5 MHz Tx to Rx Minimum. Always use Double Shielded RF Coaxial Cables. The Handheld Portables will require internal modifications for Discriminator audio output and a DC Logic Low or High to Key the other Handheld unit.

There's a possibility of using a R.I.C.K. controller board as a Squelch Gate for Analog operation. For Astro, you probably would require some reclocking in the Digital path.

Another item you will need think about are the DC Voltage requirements by the Handheld Portables and if you intend to operate the portable repeater for any lenght of time at a site without an external AC/DC power source to supply power to the repeater package. I would suggest a minimum of a 12V DC @ 20 A/H Battery with the appropreiate voltage regulators for the Handheld Portables.

Keep a distance of 1 Foot Minimum Separation between the Handheld portables so the units do not cause internal intererence to each other due to the synthesizers.

Tests have been performed 25 years ago that a Portable Repeater Package have generally 1~2 dBm of Desense due to the nature of the design and packaging.

Dan562 wrote:Tests have been performed 25 years ago that a Portable Repeater Package have generally 1~2 dBm of Desense due to the nature of the design and packaging.

Hi Dan.

"dBm" is an absolute power measurement (the measured power value compared and referenced ratiometrically to 1 milliwatt, which is 0 dBm) and-

"dB" is strictly a ratio (IOW not an absolute power measurement.)

+- 1 to 2 dBm of desense would be in the vicinity of 1 milliwatt of desense with receivers that are generally in the -120 dBm sensitivity range! (One dBm of desense would be a boatload of desense.)

Regards,

Jim (designer of the Heliax 'stub' Six Meter Duplexer)