Archived posting to the Leica Users Group, 2003/05/15
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Jim Bickerton wrote: >I have recently acquired a used R8, which works OK except for the flash. > >The flash gun (an inexpensive one) should work from the hot shoe, >according to the R8 manual. > >What happens is that if the flash gun is charged as I fit it to the hot >shoe, it flashes immediately. After it recharges, no amount of shutter >releasing or pressing the depth of field lever causes the flash to go off. > >Any ideas? Jim: Sounds to me like the flash contacts are fried. Modern (electronic) cameras have an upper tolerance for voltage of between 5 and 15 volts. However, older, inexpensive guns often have trigger voltages over 300 Volts. One, 20 year old Vivitar 265 measured out at 750 Volts! If such flashguns are used on a modern electronic camera, the circuit gets fried and you have results similar to what you're getting. More modern flash guns are designed with a low voltage trigger circuit. How do you tell? With the flash gun off the camera, turn it on until the ready-light has been lit for a few seconds. With a multi meter (set to 1000V if not an auto-ranging model) and put one pin on the ground (usually on the side of the hot shoe) and the other on the central pin of the hot shoe. Read the voltage. If it's over 20 Volts, that's likely your problem! Of course, it's possible that your problem may have been caused the same way, but by the previous owner! If you want more info on this, check out: http://www.people.smu.edu/rmonagha/mf/flash.html I hope [a] this helps and [b] that this isn't your problem! Could be expensive if it is. Cheers! - ---------- David Young | A man who gives in when wrong - is wise. Victoria, CANADA. | A man who gives in when right - is married. Website at: http://www.horizon.bc.ca/~dnr/ - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html