*(My notes are at the end of this file) Copyright © 1999 * * The Kenwood TM-G707E is a wonderful rig and it's ability to name * memories is a nice feature, if it could all be programed by a * computer... * * The software is available to anyone on the Kenwood web-site, all that's * needed is the cable to connect to the computer. I have absolutly no * idea what Kenwood put inside the origional PG-4S cable, however when * the TM-G707E is put into Clone-Mode and you examine the signal from the * Mini-DIN, it's clear that the cable electronics must handle TTL/RS232 * conversion. The circuit described below fulfills these functions for me, * with no compaints. I think the TM-V7E operates the same way. * * How it works: * Connecting Pins 4 and 5 tells the kenwood to switch from FSK to serial * operation. The PC pulls the RxD-input on the kenwood low via R5 and T2, * obviously there's an internal pull-up. * * On the other hand, the connection from the Kenwood to PC is more * difficult, the Kenwood offers only one TTL-Signal, the serial input on * the PC, however, expects to see two levles, about 10V +/-. There must * be two signals. * * Via R1, a positive signal from the PC's RTS is seen and stabilized * by D1 and C1. A negative voltage is achieved from the PC's TXD signal * via D3 and R6 and is buffered by C2. Then the Kenwood can now send data * with T1 switching between positive and negative voltages. * * I stuffed the whole thing in a Sub-D connector hood. * * 'Wulf' wishes you lots of fun with it, DB8KY * * Whoever uses a device made with these plans does so at their own risk * * ::pg4s.jpg:: * * R1/R6 = 150 Ohm * R2 = 22k Ohm * R3 = 10k Ohm * R4 = 33k Ohm * R5 = 15k Ohm * C1/C2 = 1uF/16V Electrolytic * D1 = Zener Diode 5.1V * D2/D3 = 1N4148 or similar * T1 = BC558A or similar * T2 = BC337 or similar * ******************************************** * KC7ZRU's Notes (using TM-V7A):* * * These are the Radio Shack Part numbers for the cable I built: * R1/R6 = 271-1312 (150 Ohm) * R2 = 271-1128 (22k Ohm) * R3 = 217-1126 (10k Ohm) * R4 = 271-1129 (33k Ohm) * R5 = 271-1127 (15k Ohm) * C1/C2 = 272-996 (Non-polarized electrolytic) * D1 = 276-565A (1IN4733A 5.1-volt Zener Diodes) * D2/D3 = 276-1620 (1n914 Type (50)) * T1 = 276-1604 (2N3906-Type Transistors) * T2 = 276-1617 (NPN-Type switching transistors) * * Extras: * Aluminum Project enclosure 270-235 * 6-Pim Mini-DIN Male Plug 276-1474 * Metalized Hood (DB-9) 276-1513 * DB-9 Female 276-1538C * PC Project board 276-0418 * 6-32 Rnd hd machine screws 640-3012 * 6-32 Hex nuts 640-3019 * 8' of 4 conductor modular phone cable. * Shielded cable would be better. 3 conductors and shield on * the PC side, 2 condctors and shield on the radio side. * * Mini-DIN pin numbers shown in the schematic are the EXACT same as * the diagram on page 80 of the TM-V7A Manual. Don't transpose them at * all. If you don't have the manual, get one at the Kenwood Web site. * * When using the RS Mini-DIN plug, don't bother using the slip on * boot. About 4 inches of black electrical tape wrapped around the * plug body will hold it together and allow it to fit in the data * port of the radio. * * Make sure the VHF/UHF chanel ration in the software matches what your * radio is set to BEFORE trying to write to the radio. I wasen't able * to get my setup to delete existing information from a memory chanel. * Would write new data into a memory fine, even into a memory chanel * that had other data in it already. Just wouldn't replace existing info * with 'null' info. *======================================================================= * This English Interpretation Copyright © 1998, 1999 by Tate Belden * and may not be duplicated, published or re-distributed in any form * without specific written permission. * All rights reserved. * Schematic drawing is Copyright © 1999 by Keith Casey, copied here * with permission. * * This interpretation provided as is, and should be accepted and used * without expecting any particular fitness for any particular purpose. * No liability is assumed with respect to the use of any of this *information