Kenwood TH-D7E - Back from the USA
Introduction
A member of the radio club had purchased a Kenwood TH-D7E. Unfortunately it did not have the correct UK repeater offsets and band ranges. This made it very awkward to use.
Some investigation confirmed that it was the European E version, but setup for the American repeater offsets and band plan. Having previously modified my Kenwood TH-F7E for wide band RX by removing a diode it seemed likely that similar fate had befallen this radio - but in the direction of America.
I briefly looked at the Kenwood memory programs, just to see if the modification could have been done in software. This confirmed the radio had indeed been modified for America, as the UK program would not even recognise it - the American version worked fine. I reset the radio to its factory setting and as expected it remained on the other side of the pond.
To Europe
The Kenwood TH-D7 Yahoo Group files section had full details of the diode configurations for the various regions.
Diode X=Absent O=Present
|
DIODES |
RX | RX | TX | TX | Default | RX | RX | TX | TX | Default |
2m Offset |
70cm Offset |
Tone 1750 |
Skycommand & Remote |
VHF Narrow |
REMARKS / 118-136MHZ |
|
XOOO |
144 | 146 | 144 | 146 | 144 | 430 | 440 | 430 | 440 | 430 |
.6 |
1.6, -7.6 |
Yes |
No |
Yes* |
EUROPE GENERAL / N |
|
XOOX |
136 | 174 | 136 | 174 | 144 | 400 | 480 | 400 | 480 | 430 |
.6 |
1.6, -7.6 |
Yes |
No |
Yes* |
EUROPE EXPANDED RECEPT./Y |
|
OOOO |
136 | 174 | 144 | 148 | 144 | 400 | 480 | 430 | 450 | 440 |
.6 |
5 |
No |
Yes |
No |
USA - CANADA/Y |
*TH-D7E Hardware Required for this function
Only top (left) most diode had to be removed to restore the
radio to the European configuration.
After removing the four rear screws, knobs, retaining nuts and top cover I tried to carefully prise apart the two parts of the radio, but despite my best efforts it came apart rather too quickly and in the process pulled the ribbon connector from the front board. This is not ideal, and really should be avoided..
I carefully checked the diode to be removed, it was a different size and had been hand soldered, this provided further confirmation of the original configuration. A quick dab to either side of the diode with the soldering iron and it stuck to the tip enabling easy and clean removal. Checked the board for shorts or debris.
Carefully inspected the ribbon cable connector, eased the cable back in and then pressed the retaining clip down. It seemed square and secure.
Testing
Switched on. The resetting message appeared - so at least the ribbon connector was OK! A quick spin around confirmed that we were safely back in Europe. Excellent.
Photo sequence
