YS110 is not YS110a!

Yet again I learned that one of my assumptions was incorrect. SEA & SEA YS110 and YS110a strobes do not behave the same!

I had a pair of YS110 strobes (original owner, pristine condition, a few cosmetic scratches on the housings,willing to sell...) as well as a pair of the follow-on YS110a's (purchased used on eBay - really hammered, they look like they had been dragged behind a pickup truck for a few miles, I would be embarrassed to re-sell...but they work just fine).

The YS110 and YS110a are physically very similar. The talk at the time was that the YS110 had an engineering design flaw that led to poor optical triggering performance (I agree...) and the YS110a was a quick re-issue new model to solve the problem. They both feature 3 flash tubes and the same set of controls. Except the power setting knob on the YS110a had ribs on it and rotates in the opposite direction. For the YS110 "FULL" power is fully counter clockwise. YS110a "FULL" power is fully clockwise.

I had performed all of my initial controller research using a few ancient YS50 strobes. They were purchased real cheap via eBay. Expendable. When it came time to finally create a useable Quench controller I dragged out my current strobes. At that time I was using my YS110's as my main set of strobes. These were part of the bundle of my original purchase of a DX-1G setup. I later purchased a used YS90DX from eBay as a backup strobe. I never used the YS90DX strobe underwater, but on 1 dive trip I did lend it to another diver when they had a failure of one of their YS-D1 strobes. He noted that the opposite rotation of the power knob issue took a few dives to get used to. My pair of YS110a's were purchased afterwards as a potential replacement for my YS110s if they failed. The price was right.

This meant I started testing with my prime YS110s, But while I was coming to grips with the non-linear discharge curve world, I did a random swap with the YS90DX and eventually ended up with the YS110a's for my final calibration tests. So the set of prior posts titled YS110 calibration should really have been titled "YS110a Calibration".

I was alerted to my potential mistake a few days before my dive trip to try out the controller. A post on Scubaboard (or wetpixel?) regarding a YS250 TTL converter caused me to (re)read the manuals for the Sea and Sea TTL N and C converters. I discovered that the YS110 and YS110a required different settings. SEA & SEA documented that the YS110 and YS110a were different.

From the TTL converter manuals, the A, B, C, D setting switches correspond to the following strobes:

  • A: YS110a, YS120
  • B: YS250
  • C: YS90auto, YS90dx, YS90duo, YS60N
  • D: YS110

I was surprised. I had assumed the YS110 and YS110a would provide similar behaviour. Sea & Sea disagreed. They are the experts. And they are correct.

I started the dive trip using my old system without the Quench controller. Mid-week I added my Quench controller. A quick test with a YS110 revealed that it did not perform a full dump when my Quench controller was set to maximum power. Oops. My Quench Controller was programmed for YS110a strobes only. No panic, I packed the YS110's away and dragged out the YS110a's for the rest of the week. Good thing I drag way too much extra stuff on my dive trips...