The interfaces found on this page can be used for many ham radio programs such as: MMSSTV, EasyPal, FRN, Eqso and Echolink
Basic com port PTT Interface for base / mobile radio
Isolated audio & Keyer Interface for base / mobile radio "it is best to isolate the audio"
Simple Interface for base / mobile radio
Simple Interface for Handheld Radios
Transformer: The type of transformer is determined by the source of the RX audio.
If you take it from the radio's microphone or data jack, you'll use a 600 to 600 Ohm (1:1)
transformer. If you take it from the radio's speaker jack (8 Ohm impedance), you'll need a 1000:8 transformer.
R1 = Resistor, e.g. 1K2, to reduce voltage on the IC pin 1
IC = Integrated Circuit; this sketch shows an IC, such as a 4N33
or PS2603 Optocoupler, which uses a Darlington pair transistor.
(Note: to identify pin #1, look for a small embossed circle on
the top of the IC above pin 1; or looking into the notch in one
side of the IC with the pins down, pin #1 is to the right of the notch.)
D1 = Diode, e.g. IN4001, would shunt any potential reverse voltage
that might damage the sensitive diode/emitter in the IC.
(Note: the band printed on the diode marks the cathode end,
which attaches to the Serial Port/IC Pin 1 line in the sketch above.
The opposite/anode end attaches to Ground.)
The ideal components for your circuit may vary because of your radio's requirements.
For example, you might be able to use a different type of IC, such as a 4N25 or PS2601, but that may require a different value for R1.
Use the RTS ( Request to send ) pins NOT the DTR ( Data terminal ready ) pins
On a DB 9 Serial connector use RTS pins 7 ( PTT ) & 5 ( Ground )
On a DB 25 Serial connector use RTS pins 4 ( PTT ) & 7 ( Ground )
Here is some HT interfaces
And if you just can't be bothered!
There is a guy in the UK that builds good quality ready built Interfaces with isolating audio transformers and PTT switching ready wired to your radio for £26.50 plus postage you can contact Alan M0AQC HERE
Alan is a very helpfull guy
Home * Station-Details * My-Antennas * QTH * Radio-Contacts * Links-Page * My Latest Projects * My Antennas * Latest-20m-Analogue-Images * World-SSTV-Cams * Digital 80m-SSTV Live * Digital 20m-SSTV Live * KG-STV Live * KG-STV-Tech-Info * World Digital SSTV Cams * Digital SSTV Europe * Digital SSTV USA Canada * Digital SSTV Australasia * SSTV Repeater * Other Digital Modes FreeDV * SSTV-Cams-Europe * SSTV-Cams-Australasia * SSTV-Cams-USA * SSTV-Modes-Info * Webring-Cams * Join-Webring * Slant-problems? * Build-SSTV-Site * SSTV-Graphics * Echolink-MB7ICL * APRS * APRS-Basics * Like-This-Site * Site Map * Live Webcams round UK * Ham Shack Cams * My Shack Cam * D-Star * Email-Me * SSTV-Chat * SDR radio * SDR radio on Digital Modes * Make-a-Streaming-Webcam * Live-AirNav * My-AirNav-Setup * Make-your-own-AirNav-page * Join AirNav Webring * Make-a-FREE-SSTV-Website * Make-a-FREE-Ham-Website * Make-Easypal-Streaming-Cam * Truck-Cam * RC-Models * FPV- First Person View * Anderson Powerpoles * SSTV Interface * 11m_CB_Gateway * 13cms & 23cms ATV* Slash Zero & Morse Fonts * iPhone-Apps * Android-Apps * Clacton-Radio-Club * FreeBand_Radio * World_Weather_Satellites * Sky_Box_Tricks&Tips * View and move my PTZ security camera * For-Sale * SD-Card-Formatter * Motorola-GM300-Program-Interface * Emotator-Rotators *
Check out the many links at the top of this page to find SSTV cams and SSTV software. I use Digital Master 780 but many programs are free to download inclding MMSSTV.