Msg Nr. : 61431 Da : IW2GUR Per : 9600 @ITA Tipo/status : BF Data/ora : 1105/0914 Dimensione : 1839 Titolo : Modifica 9600 baud per TH 75 Bid (Mid) : 77912_IW2GUR Ciao a tutti, alcuni giorni or sono e' circolato in rete un bollettino di richiesta della modifica a 9600 G3RUH al portatile Kenwood TH75. Quale possessore di tale portatile mi sono messo alla ricerca dei segnali necessari con ottimi risultati. Occorre innanzitutto aprire il portatile e localizzare le tre schede: IF UHF UNIT (X58-3610-00) sul pin 11 del RCL 10485 RX UHF IF VHF UNIT (X58-3610-01) occhio, e' sotto un lamierino da dissaldare delicatamente !! Sul pin 11 del RCL 10485 RX VHF MIC AMP (X58-3620-00) Sul pin 8 della scheda, quello verso il pacco batteria, c'e' il segnale per TX sia VHF che UHF a seconda della banda selezionata. Per i PTT non esistono problemi, basta dare un'occhiata allo schema per localizzare piu' di un punto sotto la scheda. Tutto qui, mi raccomando delicatezza, saldatore a punta finissima e tanta pazienza. Bye VALE IW2GUR@IW2GUR.ITA.EU Msg Nr. : 63358 Da : IW5DAG Per : 9600 @ITA Tipo/status : BF Data/ora : 1108/1845 Dimensione : 6084 Titolo : Modifica 9600 baud per TH 75 Bid (Mid) : 50745_IK5MEP John, Heres another one to add to the collection. 73 Richard G3RWL This is for the TH75E (dual band) hand-held. Some folks may wonder why use a handy-talky for satellites ? - well, the PA transistor blew on my IC-471 and I needed to stay QRV if possible while it went away for servicing; this provides a crude way of doing so, but you need steady hands, confidence, a low-power fine-tipped soldering iron, and knowledge that if you make a mistake it could be expensive and I won't pay the repair bill. Remove the battery. Remove the two screws thus exposed into the front panel. Next remove the screws (2) above and below the PTT switch. Finally remove the single screw beside the wrist-strap anchorage. Thats five screws in all, front panel removal is also explained on page 31 of the TH75 manual (for installation of optional CTCSS unit). Since the TH75 is a dual band rig, there is a separate IF module for each band; the VHF one is screened but the UHF one is not (I don't know the reason for the difference). Discriminator output is taken from the UHF module as below and is adequate (a couple of volts) to drive the G3RUH 9600bps modem. A lower level output (but not enough for my RUH9600) is available from the CTCSS option connector pins 9 (signal) and 10 (ground); when CTCSS is not fitted, this connector has a resistor pushed into it between pins 5 and 10. = = = | | | | | | | | | | | | ------------------- screw ---> | | <--- screw | |--------|| fold front P| | || <--- VHF IF unit (screened) panel to T| |--------|| this side. T| | | |--------|| screw ---> | | || <--- UHF IF unit (not screened) | |--------|| see expanded view below | | | | \ TH 75 / | below | | control | | panel | | | | | <--- exit for THIN cable --------------- ^ 2 ^ |---screws--| On the IF module pcb you'll see a small potentiometer at the left-hand end, some components, an IC, and a 455 filter module; all surface mounted with tiny solder connections to the board, thats why you need a fine-tipped iron and a steady hand. Raw discriminator output comes from the top left pin of the IC to the top of the chip capacitor immediately beside it; thats where I wired to, taking ground from the left-hand end of the array of connections to the motherboard. I used two strands of thin ribbon cable for this (screened cable would be too thick), fed the cable downwards and came out just below the DC IN connector to a free phono connector. Then I used screened cable out to the modem. All the screws go back easily except the one nearest to the output wire; I GENTLY squeezed the two halves of the rig in a vise until the two holes lined up then put the screw in. Discriminator output, ------------ connect to this end of this tiny chip capacitor \|/ ----------+------------- | r c c ----- |---|| UHF IF module |pot e a a |d c| -----| ============= | s p p |i h| | 4 || | |s i| | 5 || | |c p| | 5 || | ----- -----| | o o o o o o o o o | ------------------------ ^ |---------- ground Operation: Set the rig to 5KHz steps (the smallest possible). Take coaxial cable from the antenna connector to your normal antenna feedline. Optionally set the squelch as desired. Use it. I find that mostly I get a solid DCD indication and good data. What with 5KHz steps and the rather crude S-meter its not as good as a REAL receiver but its a fair substitute if nothing else is available. I don't change anything until the DCD led starts to flicker; then, with no centre-zero meter, you have to make your own guesses about whether to move a 5KHz step, swap polarization, swing the beam, etc. A tip; the receiver is pretty sensitive and I found I got better results with my mast-head pre-amplifier switched off except close to AOS/LOS - probably due to cross-modulation from local cellular phones. Don't forget to re-charge the battery sometimes if you're not using an external dc supply !!! Msg Nr. : 90298 Da : I2XPY Per : TUTTI @ITA Tipo/status : B$ Data/ora : 0101/0305 Dimensione : 1734 Titolo : Modifica 9600 baud per TH75 Bid (Mid) : 92751_IW1BRX Signori!!!! A riguardo dell'apparato TH75E per poterlo utilizzare a 9600Bps. Localizzare sulla PC BOARD (X57-3370-XX) (B/3) IL CONDENSATORE ELETTROLITICO C41 ,SUL SUO NEGATIVO E' PRESENTE IL SEGNALE RX PER POTERLO USARE SIA IN -UH F-CHE IN -VHF- PROVENIENTE DAL DISCRIMINATORE. (Il condensatore si trova in alto a destra.) - Per il TX COLLEGARSI SUL LATO POSITIVO (+) DEL CONDENSATORE ELETTROLITICO C2 1 PRESENTE SULLA STESSA PC BOARD(X57-3370-XX) (B/3) che e'il segnale per il VCO che fa capo ai diodi varicap sia per L'-UHF- che per la -VHF-. (Il condensatore C21 si trova in basso a sinistra. - Un po' di attenzione quando smontate il th75e ,non abbiate fretta ,punta del saldatore piccola, il forellino per l'uscita del cavo sia per la ricezione che per la trasmissione molto piccolo (IN OGNI CASO IL CAVETTO GROSSO NON PA SSA HIHI). Consiglierei di uscire in basso in modo che la parte cavo tx sia corta e non vada troppo in giro per l'apparato. Buon divertimento e buon ANNO..73.I2XPY 旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커 � 넴 � ********** 73's da Nelson I2XPY posta app.a IW1BRX ********** 넴 � 넴 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸� 賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽 Msg Nr. : 142586 Da : IW3GRX Per : TEMP Tipo/status : PN Data/ora : 0129/1240 Dimensione : 6236 Bid (Mid) : 11514_IW3GRX Titolo : Modifica 9600 baud per il TH75 **************************************************************************** John, Heres another one to add to the collection. 73 Richard G3RWL This is for the TH75E (dual band) hand-held. Some folks may wonder why use a handy-talky for satellites ? - well, the PA transistor blew on my IC-471 and I needed to stay QRV if possible while it went away for servicing; this provides a crude way of doing so, but you need steady hands, confidence, a low-power fine-tipped soldering iron, and knowledge that if you make a mistake it could be expensive and I won't pay the repair bill. Remove the battery. Remove the two screws thus exposed into the front panel. Next remove the screws (2) above and below the PTT switch. Finally remove the single screw beside the wrist-strap anchorage. Thats five screws in all, front panel removal is also explained on page 31 of the TH75 manual (for installation of optional CTCSS unit). Since the TH75 is a dual band rig, there is a separate IF module for each band; the VHF one is screened but the UHF one is not (I don't know the reason for the difference). Discriminator output is taken from the UHF module as below and is adequate (a couple of volts) to drive the G3RUH 9600bps modem. A lower level output (but not enough for my RUH9600) is available from the CTCSS option connector pins 9 (signal) and 10 (ground); when CTCSS is not fitted, this connector has a resistor pushed into it between pins 5 and 10. = = = | | | | | | | | | | | | ------------------- screw ---> | | <--- screw | |--------|| fold front P| | || <--- VHF IF unit (screened) panel to T| |--------|| this side. T| | | |--------|| screw ---> | | || <--- UHF IF unit (not screened) | |--------|| see expanded view below | | | | \ TH 75 / | below | | control | | panel | | | | | <--- exit for THIN cable --------------- ^ 2 ^ |---screws--| On the IF module pcb you'll see a small potentiometer at the left-hand end, some components, an IC, and a 455 filter module; all surface mounted with tiny solder connections to the board, thats why you need a fine-tipped iron and a steady hand. Raw discriminator output comes from the top left pin of the IC to the top of the chip capacitor immediately beside it; thats where I wired to, taking ground from the left-hand end of the array of connections to the motherboard. I used two strands of thin ribbon cable for this (screened cable would be too thick), fed the cable downwards and came out just below the DC IN connector to a free phono connector. Then I used screened cable out to the modem. All the screws go back easily except the one nearest to the output wire; I GENTLY squeezed the two halves of the rig in a vise until the two holes lined up then put the screw in. Discriminator output, ------------ connect to this end of this tiny chip capacitor \|/ ----------+------------- | r c c ----- |---|| UHF IF module |pot e a a |d c| -----| ============= | s p p |i h| | 4 || | |s i| | 5 || | |c p| | 5 || | ----- -----| | o o o o o o o o o | ------------------------ ^ |---------- ground Operation: Set the rig to 5KHz steps (the smallest possible). Take coaxial cable from the antenna connector to your normal antenna feedline. Optionally set the squelch as desired. Use it. I find that mostly I get a solid DCD indication and good data. What with 5KHz steps and the rather crude S-meter its not as good as a REAL receiver but its a fair substitute if nothing else is available. I don't change anything until the DCD led starts to flicker; then, with no centre-zero meter, you have to make your own guesses about whether to move a 5KHz step, swap polarization, swing the beam, etc. A tip; the receiver is pretty sensitive and I found I got better results with my mast-head pre-amplifier switched off except close to AOS/LOS - probably due to cross-modulation from local cellular phones. Don't forget to re-charge the battery sometimes if you're not using an external dc supply !!! ****************************************************************************** Signori!!!! A riguardo dell'apparato TH75E per poterlo utilizzare a 9600Bps. Localizzare sulla PC BOARD (X57-3370-XX) (B/3) IL CONDENSATORE ELETTROLITICO C41 ,SUL SUO NEGATIVO E' PRESENTE IL SEGNALE RX PER POTERLO USARE SIA IN -UH F-CHE IN -VHF- PROVENIENTE DAL DISCRIMINATORE. (Il condensatore si trova in alto a destra.) - Per il TX COLLEGARSI SUL LATO POSITIVO (+) DEL CONDENSATORE ELETTROLITICO C2 1 PRESENTE SULLA STESSA PC BOARD(X57-3370-XX) (B/3) che e'il segnale per il VCO che fa capo ai diodi varicap sia per L'-UHF- che per la -VHF-. (Il condensatore C21 si trova in basso a sinistra. - Un po' di attenzione quando smontate il th75e ,non abbiate fretta ,punta del saldatore piccola, il forellino per l'uscita del cavo sia per la ricezione che per la trasmissione molto piccolo (IN OGNI CASO IL CAVETTO GROSSO NON PA SSA HIHI). Consiglierei di uscire in basso in modo che la parte cavo tx sia corta e non vada troppo in giro per l'apparato. Buon divertimento e buon ANNO..73.I2XPY 旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커 � 넴 � ********** 73's da Nelson I2XPY posta app.a IW1BRX ********** 넴 � 넴 읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸� 賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽賽 ******************************************************************************* Msg Nr. : 225922 Da : DL8FCL Per : 9600BD@WW Tipo/status : B$ Data/ora : 0819/0630 Dimensione : 3538 Bid (Mid) : 1885DB0AISP2 Titolo : Modifica 9600baud per TH75 9600 baud with the TH 75. I tested the follwing modification only for the 430 MHz part. Perhaps it works also on 2 meters if you try the modification on the 144 MHz IF-Unit. For opening the TH 75 follow the instructions of the manual page 31 ( installation of the TSU-Unit ). After opening the handy, it is not necessary to disconnect any connectors between the front and rear part. All connections have to done at the rear part. -TX- On the right side of the open handy is a connector (No. 201). The wires of this connector are leading to the lower board of the rear Part. Disconnect this connector. Next remove the five screws holding the upper board. Now it is possible to lift this board for about 5 mm. On the lower side of the board are the solder pins of the connector which was opened before. Solder a thin wire to pin No 5. (Start counting at the antenna side of the TH 75). This wire can be connected direct to the TX-Exit of your TNC, if this exit has A/C level only. If the TNC has also D/C level add a capacitor of about 4.5 to 6.8 uF. -RX- A little bit higher to the connector were the TX line was connected is the UHF - IF unit (X58-3610-00). It is a small additional board over the main board. You will find the IC TK10485M on this small board. Solder a wire to pin No 11, the first one the left side (Start counting again at the antenna Side). This pin is connected to a capacitor. In order to prevent the IC from being demaged, I recomment to do the soldering at this capacitor. This wire can be connected direct to the TNC. If you need for some reason the squelch of the TH 75 during 9K6 operation, add a resistor of 10 KOhms in the RX line. These are all modifications necessary for 9K6, and now you can start closing the TH 75. If you do not install the rubber cap of the DC IN Terminal, you have a fine little gap for the wires. But it is also possible to install an additional jack if the TSU-6 unit is not installed. The ground connection can be made via the speaker jack. The PTT line of the TNC should be connected to the MIC jack. The TH 75 is able to work with a TX-Delay of 150 - 170 ms (> T15) which is a good value for a modified PLL TRX. If you have any question, send a message to my BBS. 73, Walter DL8FCL @ DB0AIS.#HES.DEU.EU