Difference between revisions of "MX800"
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= General Info = | = General Info = | ||
| + | Most amps now are wide band, but I've seen a number that do not have the discrete driver transistor. They have a Mitsubishi power module as the first stage and three tuning capacitors. When peeked for maximum power (~60W) they have a 2% bandwidth. As they were tuned for 218 MHz from the factory it's worth retuning for amateur band operation. This will improve the match, which is important when followed with a duplexer. | ||
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| + | These 218 MHz amps are not happy doing less than about 25W. Some have displayed spurious emissions when operated out of this 25-50W envelope. | ||
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| + | The below was a soft amp. | ||
I've found the power out to drop off to less than 50 W (40W normal) at 225 MHz. The MX800 doesn't appear to have a loop power control. Not sure what causes this, but I'll need to test further. | I've found the power out to drop off to less than 50 W (40W normal) at 225 MHz. The MX800 doesn't appear to have a loop power control. Not sure what causes this, but I'll need to test further. | ||
| + | = Interfacing = | ||
| + | |||
| + | More coming | ||
| + | |||
| + | = DCS Decoder = | ||
| + | |||
| + | The DCS decoder works, but the CTCSS led doesn't turn on if it's received. The only indication is the M-LEAD which can be configured to be ALARM-1 or M-LEAD. This output is open collector (shorts to ground) when squelch is open and a configured CTCSS or DCS tone is received. | ||
| + | IC18 is the output latch for the LEDs and pin 12 will go high when M-LEAD is active. This is a convenient place to get an active high for DCS/CTCSS active. | ||
[[media:MX800-F 220 MHz Technical Brief.pdf|MX800-F 220 MHz Technical Brief]] | [[media:MX800-F 220 MHz Technical Brief.pdf|MX800-F 220 MHz Technical Brief]] | ||
Revision as of 00:46, 27 April 2017
Information on the MX800 Base Station from Spectra Engineering
General Info
Most amps now are wide band, but I've seen a number that do not have the discrete driver transistor. They have a Mitsubishi power module as the first stage and three tuning capacitors. When peeked for maximum power (~60W) they have a 2% bandwidth. As they were tuned for 218 MHz from the factory it's worth retuning for amateur band operation. This will improve the match, which is important when followed with a duplexer.
These 218 MHz amps are not happy doing less than about 25W. Some have displayed spurious emissions when operated out of this 25-50W envelope.
The below was a soft amp. I've found the power out to drop off to less than 50 W (40W normal) at 225 MHz. The MX800 doesn't appear to have a loop power control. Not sure what causes this, but I'll need to test further.
Interfacing
More coming
DCS Decoder
The DCS decoder works, but the CTCSS led doesn't turn on if it's received. The only indication is the M-LEAD which can be configured to be ALARM-1 or M-LEAD. This output is open collector (shorts to ground) when squelch is open and a configured CTCSS or DCS tone is received.
IC18 is the output latch for the LEDs and pin 12 will go high when M-LEAD is active. This is a convenient place to get an active high for DCS/CTCSS active.
MX800-F 220 MHz Technical Brief
Docs
Software
MXtools is the software used to manage the radios.
MXtools V3.1.8028 - Needed for >3.6.0 Firmware.
All these need a password to program the radios, and have different access based on the password used.
'solder' - basic password, lowest access 'solderall' - more advanced password 'solderadv' - more advanced, looks like you can change the model number using this and the channels from narrow/wide 'solderusa' - not sure 'solderalllc' - looks to be the best
Firmware
The firmware sits on a 27C512 64k byte EPROM.
Release notes MX800 Firmware History.txt
Spectra mx800 27c512 firmware image v2.9.6.bin
Spectra mx800 27c512 firmware image v3.0.5.bin
Spectra mx800 27c512 firmware image v3.1.02.bin
Spectra mx800 27c512 firmware image v3.2.5.bin
Spectra_mx800_27c512_firmware_image_v3.5.7.1.bin
Spectra_mx800_27c512_firmware_image_v3.5.14.0.bin
Spectra_mx800_27c512_firmware_image_v3.6.4.2.bin
Spectra_mx800_27c512_firmware_image_v3.6.5.00.bin
Spectra_mx800_27c512_firmware_image_v3.6.8.00.bin
Spectra_mx800_27c512_firmware_image_v3.7.1.2.bin
Spectra_mx800_27c512_firmware_image_v3.7.5.0.bin
Spectra_mx800_27c512_firmware_image_v3.8.0.0.bin
