Telling the difference between q2439A and B?

[BirdShot]

HI all.

I was wondering how to tell the difference between these two duplexers.

I see no visible part number on the three I have in stock, and when I pop them into a 4200 and run a config, it just says "duplexer".

:confused:

Thanks,

BS

[MichaelTech]

the 4200\4300 use the A, and the 4250\4350 use the B
It is a speed and timing issue.

[BirdShot]

Thanks for the reply, but perhaps I was unclear -

While I know the two models aren't compatible, I'm wondering how to tell them apart - e.g. I have four duplexers on a shelf and the part number isn't on them (as far as I can tell) so how do I know which is an A model and which is a B model?

Thanks again.

BS

[redcow]

If serial numbers are present, call HP for description.

[ptjeff1]

I just looked at both Q2439A and Q2439B. The A version only works in the 4200 & 4300, the B version in 4200, 4300, 4250, 4350. When we plugged in the A version in to a Laserjet 4250 there was a bad duplexer connection error. The connectors physically look the same but I didn't bother taking it apart to further investigate.

The stickers on our Q2439A's have the numbers R73-5053, RU5-8086.
The stickers on our Q2439B's have the numbers R73-5047, RL1-4088.