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Kenwood TH-F7E Interface

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

Kenwood TH-F7E Circuit Board Closeup

1. Remove the knobs, retaining nuts and 4 rear screws
Kenwood TH-F7E Circuit Board Closeup
2. Remove the top cover and carefully prise apart
Kenwood TH-F7E Circuit Board Closeup
3. Open up - careful with the rubber seal and the ribbon cable!
Kenwood TH-F7E Circuit Board Closeup
4. Diode to be removed is directly above the three diodes marked A