I had asked earlier if anyone had tried this chip to correct run-away power on a VHF MaxTrac, I got no response so I assume not.
So here's my review.
Radio Tested:
Motorola MaxTrac
MODEL# D43MJA7DA5_K
Cut: 146-176MHz
45 WATTS
16 CHANNELS
Logic Board HLN9313B
16-pin accessory connector
Firmware Chip C. 1990, Vs. 5.34 HLN5569A
Testing: Amateur Bands Firmware Chip 5.34
NOTE: This chip IS NOT for the MaraTrac or the 99 ch MaxTrac
Amateur Bands Firmware Chip 5 34 for Maxtrac 2 Meters 6 Meters or 10 Meters | eBay
I took the sellers advice and made sure the radio was in good working order and that the VCO would lock in the 144 to 146mhz range, (even if the power went nuts) otherwise it would require the VCO to be realigned and probably a full "board replacement" procedure to be preformed. He also told me that in some rare cases the deviation may need to be adjusted even if the VCO's fine, but for this chip swap there was a way to do it without any sophisticated test equipment.
Equipment used:
MJF 260C Dry Dummy Load
Workman mod104 SWR/Watt meter, 150 watt range.
I took power readings before and after installing the new chip. The Workman SWR/Watt meter isn't known for its accuracy, so numbers shown are for comparison only.
Freq........OEM Chip.....Custom Chip
155.50........48w.............45w
146.00........50w.............45w
145.50........Pegged.......45w
145.00........Pegged.......45w
144.75........Pegged.......45w
144.50........Pegged.......45w
144.25........Pegged.......45w
144.00........Pegged.......45w
143.975......Pegged.......Pegged
After the swap I reprogrammed the radio with my favorite local repeaters, the main one being 145.110-, and talked to a fellow ham for a few minutes. He told me I sounded good, so I assume that the derivation isn't off enough (if any) to affect normal use.
I could have just did the manual power adjustment modification, but my eyesight has went downhill in the past few years and I wasn't sure I could do the soldering without f-ing something up. The $18.88 (free s&h) was worth the peace of mind knowing I wouldn't mess it up.
All in all I give it a thumbs up!
KD8VBV
So here's my review.
Radio Tested:
Motorola MaxTrac
MODEL# D43MJA7DA5_K
Cut: 146-176MHz
45 WATTS
16 CHANNELS
Logic Board HLN9313B
16-pin accessory connector
Firmware Chip C. 1990, Vs. 5.34 HLN5569A
Testing: Amateur Bands Firmware Chip 5.34
NOTE: This chip IS NOT for the MaraTrac or the 99 ch MaxTrac
Amateur Bands Firmware Chip 5 34 for Maxtrac 2 Meters 6 Meters or 10 Meters | eBay
I took the sellers advice and made sure the radio was in good working order and that the VCO would lock in the 144 to 146mhz range, (even if the power went nuts) otherwise it would require the VCO to be realigned and probably a full "board replacement" procedure to be preformed. He also told me that in some rare cases the deviation may need to be adjusted even if the VCO's fine, but for this chip swap there was a way to do it without any sophisticated test equipment.
Equipment used:
MJF 260C Dry Dummy Load
Workman mod104 SWR/Watt meter, 150 watt range.
I took power readings before and after installing the new chip. The Workman SWR/Watt meter isn't known for its accuracy, so numbers shown are for comparison only.
Freq........OEM Chip.....Custom Chip
155.50........48w.............45w
146.00........50w.............45w
145.50........Pegged.......45w
145.00........Pegged.......45w
144.75........Pegged.......45w
144.50........Pegged.......45w
144.25........Pegged.......45w
144.00........Pegged.......45w
143.975......Pegged.......Pegged
After the swap I reprogrammed the radio with my favorite local repeaters, the main one being 145.110-, and talked to a fellow ham for a few minutes. He told me I sounded good, so I assume that the derivation isn't off enough (if any) to affect normal use.
I could have just did the manual power adjustment modification, but my eyesight has went downhill in the past few years and I wasn't sure I could do the soldering without f-ing something up. The $18.88 (free s&h) was worth the peace of mind knowing I wouldn't mess it up.
All in all I give it a thumbs up!
KD8VBV
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