hp f2105 slow screen

[davg]

Re: hp f2105 slow screen

I finally got back at this monitor. I have now replaced all the caps in two of the four boards (that were all elite caps) with no results. I did find a loose connection at the main plug connection (120v) and re soldered but did not make any difference. Not sure what to try next. here is a photo of the boards I think??. My first post with attachment??

Not a good picture

[Wizard]

Re: hp f2105 slow screen

Board in center is audio processor/ampifier.

Right side is mainboard. See if you can replace some electrolytic capacitors near big chip and any capacitors around linear regulators. They may be noisy or freaking out by oscillating regulator or two.

Cheers, Wizard

[davg]

Re: hp f2105 slow screen

Board in center is audio processor/ampifier.

Right side is mainboard. See if you can replace some electrolytic capacitors near big chip and any capacitors around linear regulators. They may be noisy or freaking out by oscillating regulator or two.

Cheers, Wizard

Thanks Wizard I have replaced all the caps in the white board and the video board to the far right of it. The only caps I have nor replaced is those in the board to the left of the white board? Guess I should try these which I assumed is the inverter board and the lamps are lighting up although the video is somewhat dark? Also I have not done anything with the small board to the immediate right of the white board.

[davg]

Re: hp f2105 slow screen

The three larger caps in the inverter board are 330uf @35 volts which I do not have would a 470uf @35 be a good substitute?

[Wizard]

Re: hp f2105 slow screen

Should be fine and is low ESR with good ripple current rated, tell us what kind of capacitors you have on hand to use? And that's not inverter board, it is mainboard (right most side) I'm talking about.

I need you to get more good capacitors like from big pope or like. To replace several capacitors for the SMD voltage linear regulators, sometimes they oscillate and distort the voltages, upsetting the processing which might make it go slow.

[davg]

Re: hp f2105 slow screen

Should be fine and is low ESR with good ripple current rated, tell us what kind of capacitors you have on hand to use? And that's not inverter board, it is mainboard (right most side) I'm talking about.

I need you to get more good capacitors like from big pope or like. To replace several capacitors for the SMD voltage linear regulators, sometimes they oscillate and distort the voltages, upsetting the processing which might make it go slow.

Thanks Wizard I have now replaced all caps on all boards and the problem still persist. The caps I am using and have on hand is from here http://cgi.ebay.ca/ws/eBayISAPI.dll?...X:NEWLIST#LIST. When I replaced the caps in the mainboard (right most side) several months ago I did have one of the 22 uf @ 25 v in backwards but have since replaced it but did not make any difference. I wonder did I damage any of the other caps in that board? What I replaced were 4- 100uf@25, 9-22uf@25, 4-47uf@25 and 2-10uf @25 all of which were Lelon and Jamicon. Replacements were all equal value from the same ebay store above.

[fastvideo]

Re: hp f2105 slow screen

Hi just received a hp f2105 from my son. It powers up with full screen but the desktop is showing vertical lines from top to bottom where there is an icon even the mouse. When I move the mouse it is very slow re-acting and leaves a tail? The faster I move it the longer the tail? All action on the screen is very slow? Can someone tell me what would cause this.

I have the exact problem here, replacing new caps doesn't fix the problem, what else to check?

[EGuevarae]

Re: hp f2105 slow screen

I have the exact problem here, replacing new caps doesn't fix the problem, what else to check?

Maybe not related, but had one of the problematic units owners checked the Voltages going out of the PSU to the main board?

Also, a more detailed picture of the main board (lower right) would help.

[freelander]

Re: hp f2105 slow screen

It has been a while since this post was updated. I have an HP F2105 ripped apart right now for a different reason but there are a lot of components.

As a general question, how do you distinguish between failed capacitors and blown lamps? Mine turns on with a perfect picture then shuts off after a second or two. The previous LCD's that I have revived (with this site's help) all would shutoff after a period of time or just stop coming on. One that had a blown lamp behaved like this one.

Comments?

[EGuevarae]

Re: hp f2105 slow screen

It has been a while since this post was updated. I have an HP F2105 ripped apart right now for a different reason but there are a lot of components.

As a general question, how do you distinguish between failed capacitors and blown lamps? Mine turns on with a perfect picture then shuts off after a second or two. The previous LCD's that I have revived (with this site's help) all would shutoff after a period of time or just stop coming on. One that had a blown lamp behaved like this one.

Comments?

Test the lamps with a known good inverter or a custom-made lamp tester. That's what I do.

[freelander]

Re: hp f2105 slow screen

without asking for some spoon feeding here...do you have a design for a lamp tester? The connections on these lamps are different than other known good ones.

[PlainBill]

Re: hp f2105 slow screen

without asking for some spoon feeding here...do you have a design for a lamp tester? The connections on these lamps are different than other known good ones.

My recommendation is a 'case mod' light kit. These consist of 2 12" CCFLs in protective tubes plus a dual inverter.

As far as the different connectors - jumper wires. Make the connections with power off unless you want an unpleasant surprise.

If all monitor ccfls work properly with the kit inverter while the monitor inverter still shuts down with the kit CCFLs, the conclusion is the inverter is bad. It could be anything from a bad solder joint to a shorted transformer.

PlainBill

[EGuevarae]

Re: hp f2105 slow screen

without asking for some spoon feeding here...do you have a design for a lamp tester? The connections on these lamps are different than other known good ones.

Check this thread.

[ek2oo2]

Re: hp f2105 slow screen

This problem is not yet resolved. Happened on my Chimei too. I'm guessing it is the screen panel buffer chip problem that handles the response timing.

Any updates please, thanks..