TS-440 INFO (1/4) *************** Hints on the Kenwood ts440 Brian Kantor, WB6CYT. The TS440 is nice. Here's what I've found out about it that isn't in the operting manual( in some random order ): Diode Options: There are a bunch of configuration options controlled by clipping or inserting diodes on the back :Aadjust the Mic Gain on FM - there is a seperate tweaker for that). Serial Interface The TS440 has a serialASCII interface option. You have to insert two chips into sockets on the back of the control unit circuit board to take advantage of this. IC54 is an 8251A Uart, and IC55 is a CD4040 divider. These chips are available from Kenwood together with an interface manual, or you can buy them at your local chip shop for about $6.00 or so. When inserted, the transceiver speaks 4800 baud ascii in/out the 6-pin DIN connector ACC-1 on the rear. The signals are from the 8251, but are inverted in a 74LS04 and RFI filtered before being brought out to the world. An interface box with inverter, RFI filter, power supply, opto-isolator, RS232 level shifters, TS-440 INFO (3/4) Self Test Self-Test: You can run a rather complete test of the control logic by the built-in "semi-self-test", a series of 56 routines. To run this, turn the unit on whilst holding the AM and T\-F SET switches pushed in. It changes to the next test when you turn the VFO knob clockwise. Turn the power OFF to reset the unit. This does not destroy memory contents. TS-440 Self-Tests Test What it does 0 all positions in display light 1 all segments in display dark 2 all positions in display light 3 all segments in display dark 4 one digit lighted (rightmost) 5 next digit lighted 6 next digit lighted 7 next digit light TS-440 S MODIFICATION TO USE ANTENNA TUNER FOR XT AND RX.- Remove case from rig. Remove (4) screws that holds antenna tuner in place. Next slide antenna tuner out to get to the coax connections. Remove the in coax attached to antenna tunerfrom FO connector on filter unit (X51-1340-00). Remove coax from out connector on antenna tuner and install in FO CONNECTOR ON FILTER UNIT. Unplug and remove switch unit (X41-1610-00 N-14) from rig. Remove short wire from antenna connector to PC BOARD. Cut coax on the in connector of antenna tuner in half and connect cut end to switch unit PC BOARD Where short antenna wire was removed and shield to ground. Solder other half of coax to antenna connector and shield to ground, and plug other end into out conector of antenna tuner. Your still have control of antenna tuner with auto and thru switch. It works very well. Maybe someone can use this idea. N2EDE, R.I.. Box 680-S, Roanoke, VA. 24012 West,Gordon: "Kenwood 440 Modifications" _Popular Communica- tions_, October 1987 p. 62. Illustration captions: 1. Remove 17 screws holding on the bottom and top covers. The bottom cover comes off, and the top cover is carefully removed and put next to the radio. It is till connected via the speaker wire. 2. Gain access to the front of the unit by removing two top side screws and loosening two bottom side screws. This allows the front assembly to swing open. 3. Remove the shiny silver control board protection plate. This requires removing two screws on the top and three screws on the bottom. Lift the plate out completely.} 4. Locate diode D-80 in the bottom left-hand corner. Snip it for all-band transmit. 5. Now locate D-66 and snip. It adds 10 Hertz readout to your digital frequency display. 6. Carefully reassemble the control plate using a magnetized tiny screwdriver to hold the five tiny screws in place. Don't pinch any wires. Also, close up the front and replace the top and bottom covers with 17 screws. 7. Connect power. Depress A=B switch and turn on the power simultaneously. This resets the microprocessor for all-band transmit and 10 Hz frequency display. -- Frank W9MKV