Batboard

I won't cross post but the problems I am having are with both XTS-3000 and XTS-5000 radios in simplex secure mode. All the radios work when in clear P-25 mode perfectly,as they have the same NAC code. I have a mix of different level versions of secure boards from R2.0 to R3.55, but all have DES-XL, and some have DES-OFB and the 5000 has AES as the third algo. There is one radio that no matter what version board I put in to will not receive secure until I transmit and the other radio actually receives in secure before it will then receive the other radio. This also occurs when using the 5000 as well, but after this radio receives a secure transmission it will then receive secure until you change channel or turn the radio off/on. I have tried the different unmute rules and XL and NON-XL transmitting but to no avail. I key load the radios with a T-3011DX and have no problems as the key loader gives the tone and a pass display. Any ideas?

While this may not be the problem another question is how does the radio decide which algo it uses if you have a multi algo board in it.

To further my own post so others can find this information if needed. I now have another radio that is doing the same no secure receive prior to transmit to the other radio. The second radio also has a newer version of firmware/DSP, which after reading somewhere I think may be the problem. I read that EMC modules are good up to ver R07.xx.xx and UCM requires R08.xx.xx and up.Possibly some mismatch issue with firmware to EMC modules I have.I don't have an UCM modules to try, but I will look around and if they are cheap enough I will try that to see if the problem goes away. For now those 2 portables won't be used, too much a chance of not being heard.

After some more testing with a third radio it appears the higher version firmware R08.xx.xx radios talk to one another just fine, it's the mix of lower and higher firmware causing the issue.

Information from Repeater Builder:
"XTS 3000 UCM modules require HOST firmware > 7.xx to function. EMC secure modules with firmware (1.xx-2.xx) will function if CKR key management is DISABLED and PID key management is ENABLED in the CPS. The "V67" module is very common in the second-hand market. This module is USUALLY loaded with DES, DES-XL and DES-OFB encryption (i.e. it's a NTN9121 module without labeling). When you see one with this part number on it, you can safely assume that it's a tri- mode DES/DES-XL/DES-OFB module.

Thank you for the post it was helpful..