Hardware Side of JT65-HF
Required Hardware: HF SSB Transceiver Computer 2-6 Customs Cables Digital Interface (may not be required)
JT65 Hardware Interconnects Computer Digital Interface HF Transceiver
JT65 Hardware Interconnects – Simplest Only 2 signal paths involved Computer HF Transceiver “Mic” Speaker “Headphones” “Mic” VOX Digital Interface (Not Required) PTT
JT65 Hardware Interconnects – Simple Only 3 signal paths involved Computer HF Transceiver “Mic” Speaker “Headphones” “Mic” 7 PTT RTS PTT Serial Port Digital Interface GND PTT Gnd 5 PTT Gnd 9 Pin RS 232 Connectors Only required to generate PTT signal
Digital Interface - Simplest Diodes = any working diode NPN transistor 2.2 K 7 PTT PTT PTT Gnd 5 PTT Gnd 9 Pin RS 232 Connector Diodes = any working diode
POTENTIAL PROBLEMS: Some computers do not have a “MIC” input Tones generated by computer may not have equal amplitude May be hard to identify this problem May not be a common problem No RS 232 serial port Difficult to set MIC level to transmitter Typical computer audio out is ~2V Typical “MIC” input level is ~10mV Difficult to set MIC level to computer Don’t use JT65 software to adjust receiver audio level Ground loops
Digital Interconnects Using A USB Port Computer HF Transceiver “Mic” Speaker “Headphones” “Mic” 9 Pin RS 232 Connectors M F PTT “USB” Port Digital Interface PTT Gnd USB 2.0 to RS232 Converter Mfg: eforcity Model: PCABUSBX0049 Driver Download: http://driverdownload168.com
Digital Interconnects – Best Computer Digital Interface HF Transceiver M M Receiver Audio Out “Mic” F F “Headphones” F M M F “Mic” M F “USB” Port
Ground Loops HF Transceiver Computer V1 mVAC V2 mVAC 120 VAC Outlet Mic “Mic” V1 mVAC V2 mVAC 120 VAC Outlet
Ground Loops HF Transceiver Computer V5 mVAC V3 mVAC V4 mVAC 120 VAC Mic “Mic” V5 mVAC V3 mVAC V4 mVAC 120 VAC Outlet
Note: All voltages are 60 Hz AC Ground Loops Note: All voltages are 60 Hz AC HF Transceiver Computer Mic “Mic” V5 mVAC V3 mVAC V4 mVAC 120 VAC Outlet
Ground Loops HF Transceiver Computer V5 mVAC V3 mVAC V4 mVAC 120 VAC “Mic” Tone V5 mVAC V3 mVAC V4 mVAC 120 VAC Outlet
Ground Loops HF Transceiver “Mic” Tone V5 V4 mVAC 120 VAC Outlet
Ground Loops Note: V5 will cause 60 Hz hum on transmit signal HF Transceiver “Mic” Tone V5 Note: V5 will cause 60 Hz hum on transmit signal V5 can also cause broadband noise on transmit signal Typical microphone output level ~10 mV V4 mVAC 120 VAC Outlet
Ground Loops HF Laptop Transceiver 0 mVAC V2 mVAC 120 VAC Outlet “Mic” Tone 0 mVAC V2 mVAC 120 VAC Outlet
Ground Loops HF Transceiver Computer X X V5 = V2 – V1 V1 mVAC V2 mVAC “Mic” Tone X X V5 = V2 – V1 V1 mVAC V2 mVAC 120 VAC Outlet
Ground Loops HF Transceiver Computer Isolator V1 mVAC V2 mVAC 120 VAC “Mic” Tone Isolator V1 mVAC V2 mVAC 120 VAC Outlet
Several types of isolators: Ground Loops HF Transceiver Computer “Mic” Tone Isolator Several types of isolators: DC signals Audio signals RF signals V1 mVAC V2 mVAC 120 VAC Outlet
Digital Interface + +8 VDC for Mic 9 Pin RS 232 Connector* From To Isolation Transformer To Computer “Mic” From Receiver Audio* 1 K* M M +8 VDC for Mic Isolation Transformer 10 K 100 uF From Computer “Headphones” + MIC 1 M 50 Ferrite Choke* RED BLU PTT 5 To Mic Input* MIC GND 7 F WHT SHLD PTT GND 6 BRN 1 K* LED* Iso PTT 7 PTT 1 K From USB 2.0 to RS232 Converter 1 5 F Optocoupler 4N33 2 4 5 PTT Gnd Transformers are Mouser P/N 546-149T 600W CT/600W CT 200 Hz to 15 KHz 1 watt *: Not included in some (ie, SCI-6) designs 9 Pin RS 232 Connector*
Optocoupler Optocoupler Turn-On time <5 usec 1 5 2 4 Turn-On time <5 usec Turn-OFF time < 100 usec