Spectra VRS

tomskillman · Post by **tomskillman** » Thu Aug 15, 2002 10:24 pm

Was wondering if anyone knows where to find a VRS unit for a spectra. I've seen the pac-rt units on ebay, but they all specify syntors. I did a little web searching, but I've found very little info. Anyone who can help me out, I'd be glad to hear from you. Thanks

apco25 · Post by **apco25** » Tue Aug 20, 2002 1:38 pm

Keep looking on ebay. Myself and friend got our VRS units there. They come on with fair regularity. FYI, THe model numbers either end in SP01 or SP02. SP01 was the VRS for the Syntor X9000 and SP02 is for Spectra family of radios. They are identical except for the firmware chip so they can be swapped around for the specifc radio you need to use it on. I like mine. Its a nifty item.

tomskillman · Post by **tomskillman** » Tue Aug 20, 2002 1:40 pm

I haven't really seen them listed as whether they are SP01 or SP02...is there any way to tell them apart other than that?

apco25 · Post by **apco25** » Wed Aug 21, 2002 12:05 pm

THey are identical other than the firmware. The SP01 and SP02 designation will be at the end of the model #. The vast maority of them are the SP01 type, but like I said you can order the firmware for SP02 from motorola. About $70. Look under the spectra info here on batlabs and you'll find the VRS details.

bnn121 · Post by **bnn121** » Wed Aug 21, 2002 1:06 pm

I have one if your still intrested. The model I have is a:

T04KEA3006AASP02

Dont remember what the frequency is on. I believe I have the T-cable for it also, I'll dubble check. But I do have the unit itself.

tomskillman · Post by **tomskillman** » Wed Aug 21, 2002 1:19 pm

Is it really necessary that the Pac-RT and Spectra be on different bands? I just read that on the web site. I was planning on using a UHF Pac-RT with a UHF Spectra.

Mike B · Post by **Mike B** » Wed Aug 21, 2002 4:17 pm

tomskillman,

Yes, it is necessary to have a stock VRS on a different band from your mobile. An exception might be if you had a 15 watt or less Spectra, a VRS that was at lest 5 to 8 MHz or more away from any Spectra frequency and as much physical separation between the two antennas as possible, you MIGHT get away with a UHF/UHF.

You can modify the VRS setup from what the factory intended. Add a cavity filter or equivalent device at the VRS antenna connector. You will need one designed for mobile environments (i.e. one that will keep its tuning when bumped, heated/cooled, etc.). The filter will have some loss and may affect the range of your VRS. You will still need some minimum separation between the VRS frequency and any mobile frequency you use. The more separation the better. If you run a 110 watt UHF Spectra, you may need multiple filters, more frequency separation or both to make it work. In this case you might have to add additional shielding. If you want to help makeup for the filter insertion loss, you can bypass the VRS antenna interface circuit and replace it with the new filter(s).

The above modification suggestions are in the same realm as getting a mountain top repeater system to function. Some real world experience with repeaters, links and/or remote bases sharing the same band and installation site would teach you everything you need to know and quite possibly drive you a little bit crazy

.