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IC Decap: Motorola MC68HC11E9 8-Bit Microcontroller

This particular IC came out of a very old VHF band radio, from the early 90’s. The die was encased in a custom ceramic package, like every other IC in the radio, with a custom part number. I managed to identify it from the markings on the silicon.

Motorola MC68HC11L6
Motorola MC68HC11L6

This was a pretty powerful MCU for it’s time, with 16K of onboard ROM, 512 bytes of both RAM & EEPROM, a 16-bit timer, 8-bit ADC, SPI & a MC68HC11 CPU core.

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Wouxun KG-UV950P RF Power Measurements

Following on from the earlier power tests on my Baofeng HTs, here’s the readings from the Wouxun KG-UV950P. Power is a little lower than specified, but this is probably due to the supply voltage being a bit less than 13.8v. These readings were taken at a supply voltage of 12.88v.

The same frequencies were used, 145.500 & 433.500 for the VHF/UHF tests. For the 6/10m tests 27MHz & 50MHz were used.
The power meter was connected with 1 metre of RG58 dual-screened cable with N-type connectors.


 High


6m: 24W

10m: 23W

VHF: 38W

UHF: 24.9W


Medium-High


6m: 10.9W

10m: 9.3W

VHF: 19W

UHF: 14.2W


Medium-Low


6m: 6.8W

10m: 3.5W

VHF: 9.6W

UHF: 9.4W


Low


6m: 3.5W

10m: 1.9W

VHF: 4.8W

UHF: 4.7W

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Baofeng UV-5R RF Power Measurements

I’ve noticed that the RF power output from the Chinese radios can be quite variable from model to model, and even from individual radios of the same model & batch.
I’ve bought an RF Power meter (GY561) to do some tests on the HTs I have at present.

All tests were performed with the radio fully charged & still on the charging base, to make sure the supply voltage remained constant at 8.4v throughout the tests.
Frequencies used were 145.500 & 433.500 for VHF & UHF respectively.
The power meter was connected with ~8″ of RG174 Coax.


 High Power:


UV-5R 1 (S/N: 13U1136132):
VHF: 6.3W
UHF: 4.9W

UV-5R 2 (S/N: 13U1136114):
VHF: 6.5W
UHF: 5.2W

UV-5R 3 (S/N: 130U541416):
VHF: 7.1W
UHF: 6.3W


Low Power:


UV-5R 1 (S/N: 13U1136132):
VHF: 2W
UHF: 1.2W

UV-5R 2 (S/N: 13U1136114):
VHF: 2.3W
UHF: 1.5W

UV-5R 3 (S/N: 130U541416):
VHF: 2.7W
UHF: 2.1W