Rf-100 Timer Adjustment...

[cautery]

Thanks to EricW for cluing me in to this possibility:

Adjusting RF100 Timer FAQ

My timer was running for something like 2:15 and always finishing the 100 primers in less than a minute. (BTW, heed Eric's warning about NOT doing this mod if you don't have the requisite skills and experience working with AC electrical stuff)

When I disassembled the RF100 to look at the circuit board, it hit me that the linear trim pot on the RF100 circuit board is oriented similar to the trim pot on the PACT MkIV timer.... vertically oriented to the board and right next to a case wall... (Thanks again Eric for the clue on the MkIV timer mods).

So, I decided to drill the case to permanently expose the trim pot for adjustment. This way, I'll never have to disassemble the machine's main stud and lower unit again to adjust the time.

Here are the measurements I used (measurements described with unit assembled):

Measure up from the bottom of the case 0.927" in two places, spaced apart by at least a couple of inches... Join the two points with a pencil line.

NOW, measure IN from the side (outside eadge of the case on the right as you are looking at it) right at 0.680" along the line you just drew and draw an intersecting line at this point.

Drill a 3/16" hole at the intersection point.

NOTE: YOU MUST remove the circuit board before drilling!!! PLEASE do not try to disassemble the machine until you unplug it... double check!!!

Reassemble the unit making sure to square it up as Eric describes in the tuning tips FAQ.

Now... on my unit the MAX time was 2:34. The minimum time was 27 seconds. Your unit may be different by a bit.

Get a small standard screw driver... or better yet, use a non-conductive trim pot adjusting tool like I have from my big screen TV tweaking days.

Adjust the on-time by turning the trim pot:

1) Counter clockwise REDUCES the on time.

2) Clockwise INCREASES the on time.

BE CAREFUL and do not over torque the pot... If it has never been adjusted and the time is over 2:00, then the pot is very close to its max clockwise limit.

Move the pot a little at a time and time it with your watch... Set for whatever time you want.

Cover the hole if you want, or are worried about dust getting inside the case... Masking tape is a good alternative.

Hope this helps...

AGAIN, do NT do this if you are not confident and competent with electrical stuff!