Does anyone know if the Minolta X700 can handle a flash trigger voltage of 200 volts? I remember reading somewhere that older flash units with high trigger voltages can damage somes camera's flash circuitry.

-- Rodger B. (rb643@yahoo.com), July 04, 2000

Answers

Wein makes a "safe shoe," I think it's called, that goes in the hot shoe and reduces the voltage. Best to be safe if you know for sure the trigger voltage is 200+. You can use a voltmeter to test the flash...newer flashes have a trigger voltage from about 4-6 volts.

-- Todd Frederick (fredrick@hotcity.com), July 06, 2000.

Rodger it will handle only around 6v. Early minolta's XG series used to get damaged with 24V, I have screwed up on body when they came out. So use some sort of device to reduce the voltage and to be on the safe side an optical triggor is advisable.

-- Anil (anils@vsnl.com), July 06, 2000.

Rodger, Converting X700 <6V trigger level to handle 200V is not so difficult (if it is positive with respect to the ground - that is so if I remember correct, I used to have XD7 and XG1 both operated at 6V, otherwise you need some additional circuitry). What you need is a thyristor (SCR) that can handle voltages larger than 200V (again it should be +200V with respect to the common rail, on the fasher side).

Put a 470 kilo-Ohm resistor (assuming that gate triggering current is less than 10 micro-ampere) in series with the gate electrode and connect the gate (through the resistor) and cathode to fash trigger terminals on camera. Connect the anode and cathode to terminals on the flash unit such that the anode end is positive. Here no external power supply is needed since terminals on both X700 and the flash are active.

-- Amith Munindradasa (muni@ent.mrt.ac.lk), July 09, 2000.

To work with the X700 you need few modifications to the arrangement I suggested above. In X700 the flash triggering occurs from a pulse which goes from 6V to zero (or close to zero) which necessitates to have an additional transistor before the thyristor.

Could someone enlighten me how to put sketches in html please so that I can put the proper circuit here.

-- Amith Munindradasa (muni@ent.mrt.ac.lk), July 12, 2000.

Paramount Cords has sync cords that have the voltage reducing corcuit built into the cord. Their site http://www.paramountcords.com/

http://www.paramountcords.com/vp.htm

-- john adler (angler7876@aol.com), December 13, 2000.