Project25_MASTR
Millennial Graying OBT Guy
Had a little free time today so I began playing with my TRX-2 on a service monitor. I really just have my scanner to play with and don't really depend on listening to anything with it. Anyway, did some basic tests such as distortion, 12 dB SINAD, 5% BER (P25) and adjacent channel rejection. Tested frequencies were 40 MHz, 150 MHz, 450 MHz, and 850 MHz. I didn't have a proper isolation transformer available for an 8 ohm load so I popped the cover off and pulled a ground referenced voltage off the positive speaker lead (after first checking to make sure it was ground referenced). Due the setup, I'm going to ignore the 7% distortion measurement taken at -50 dBm on all tested frequencies. I also left the default squelch settings in place and tested with a 1000 Hz tone at 1.5 kHz deviation for analog (all FM) measurements. Completely spaced while I was performing the test that these are AM capable as well. P25 testing was rough estimation tuned to "like" audio via my uncalibrated ear using a 1011 Hz tone patter and compared to recovered audio of a XTS5000 at it's 5% BER level. All measurements were made with a R2670 service monitor calibrated October 2017.
At 40 MHz, 12 dB SINAD (FM) occurred at -117.2 dBm (.30 µV). 5% BER is around -113 dBm.
At 150 MHz, 12 dB SINAD (FM) occurred at -111.5 dBm (.59 µV). 5% BER is around -107 dBm.
At 450 MHz, 12 dB SINAD (FM) occurred at -110.2 dBm (.69 µV). 5% BER is around -107 dBm.
At 850 MHz, 12 dB SINAD (FM) occurred at -108.7 dBm (.83 µV). 5% BER is around -107 dBm.
For all bands, a 30 dB adjacent channel rejection was measured (note, narrowband).The test was performed using a R8000B (calibrated January 2018) to generate a -50 dBm signal 12.5 kHz above the base frequency and coupled to the R2670 and scanner using a T connector. The difference between the injected adjacent frequency and new 12 dB SINAD point on frequency was used to determine this measurement.
It should also be noted, it wasn't until after I had put everything away that I realized the squelch setting could be adjusted (sorry, used to testing Motorola radios and never having to mess with squelch). As a result when 5 kHz deviation was attempted, the radio would not typically unsquelch below -113 dBm (while sensitivity was looking promising).
I'll likely add to his at a later point.
At 40 MHz, 12 dB SINAD (FM) occurred at -117.2 dBm (.30 µV). 5% BER is around -113 dBm.
At 150 MHz, 12 dB SINAD (FM) occurred at -111.5 dBm (.59 µV). 5% BER is around -107 dBm.
At 450 MHz, 12 dB SINAD (FM) occurred at -110.2 dBm (.69 µV). 5% BER is around -107 dBm.
At 850 MHz, 12 dB SINAD (FM) occurred at -108.7 dBm (.83 µV). 5% BER is around -107 dBm.
For all bands, a 30 dB adjacent channel rejection was measured (note, narrowband).The test was performed using a R8000B (calibrated January 2018) to generate a -50 dBm signal 12.5 kHz above the base frequency and coupled to the R2670 and scanner using a T connector. The difference between the injected adjacent frequency and new 12 dB SINAD point on frequency was used to determine this measurement.
It should also be noted, it wasn't until after I had put everything away that I realized the squelch setting could be adjusted (sorry, used to testing Motorola radios and never having to mess with squelch). As a result when 5 kHz deviation was attempted, the radio would not typically unsquelch below -113 dBm (while sensitivity was looking promising).
I'll likely add to his at a later point.
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