Vivitar 2800, New opinion on Neon Bulb removal Options

[dkirk]

Here is some updated Vivitar 2800 discharge data, and I have changed my opinion about removal of the Neon Bulb in Vivitar 2800 slave flash units (assuming they are connected to a slave flash controller that controls charging).

Neon Bulb
While working on energy consumption measurements today, I noticed I previously neglected to test the Vivitar 2800 with the Neon Bulb removed while only using the 2800A board (2800B and 2800C boards removed). Therefore I tested this combination today, and have added the data to the chart below (top curve is the newly added data).

Removal of the 2800B and 2800C boards greatly reduce capacitor discharge as previously noted, and removal of the Neon Bulb also helps reduce the capacitor discharge rate. Elimination of the Neon Bulb does indeed disable the charge limiter circuit, but when using 4 NiMH batteries this does not appear to be a problem (capacitor does not appear to over charge). Hags member 212 mentioned that he runs his Viv 2800s with the Neon Bulb removed, and I agree with this configuration.

 Vivitar_2800_Discharge_03OC06.jpg ( 89.21K ) Number of downloads: 55

 Vivitar_2800_Capacitor_Discharge_Rev_2.pdf ( 17.54K ) Number of downloads: 26


Based on this new data, refreshing (charging) the Vivitar 2800 one time every 30 minutes for 30 seconds if it has been fully modified (470K resistor added to disable auto off, Neon Bulb removed, 2800B and 2800C boards removed) should work just fine.

If the Vivitar 2800 is not connected to a slave flash controller (example : just being used with a wein peanut), then the Neon Bulb should not be disconnected since the inverter will run continuously and this will cause premature drain on the batteries. The Vivitar 2800 consumes approximately 3.5 times the energy running the inverter continuous versus having the Neon Bulb in the circuit which controls charging.

(I will follow up with a new posting regarding my recent Vivitar 2800 energy consumption data.)

Don

This post has been edited by dkirk: Oct 4 2006, 04:36 AM

[212]

Great post Don...as usual

Member 212 warns people however, that using the 2800 with the bulb removed, and anything other than 4 NiMH batteries will likely destroy your flash, possibly the camera, and might even cause a fire!