Just wanted to add my thanks to Big-les for the advice in this thread.

My trusty Humax recently decided to throw the clock problem at me, which is especially annoying as I always seem to use this clock more than any other...

However, the surgical spirit worked a treat and the amount of gunk removed from the clock board surprised me. It took a good number of cotton buds to complete the job.

I also took an air duster to the rest of the internals and gave it a good clean out.

The Boots surgical spirit does have castor oil as well as methyl salicylate and diethyl phthalate in it but it did the trick! Just need to figure out what to use the rest of it for...

Thanks for that, when I checked the Boots surgical spirit a couple of years ago it was just a mixture of ethanol and methanol, they must have changed their brew.

Hi
have had a 9200 from the your dot and has worked fine all this time well it got the
clock problem --:-- in standby on the 26 june so clean the board
had isoclene and cotten buds 2 cleans and the board was working
thanks to Big-les for all his work

mike

Thanks for your great work on this Les.

Does anyone have any idea what on earth the 'contaminant' causing the issue is ? Mine is certainly the invisible variety. I opened my 6 year old black Humax once before which fixed it for a few months but I plan to wrestle with it again as it has come back. It is frustrating effectively cleaning in the dark. Last time I became more and more aggressive spraying my maplin electrical solvent cleaner everywhere!

Thanks

Mine seems to be recurrent. Today will be the 3rd time in 21 months.

I can only say that you must be leaving traces of the substance that causes the problem.

Martin and Coulrophobe, your boards were the first boards to be fixed by me, are your boards still working or have you had to re-clean them?

Big-les, what's the secret in getting those 3 lugs at the bottom of the front panel to slide right in? I always have trouble.

It's been two years since I had my 9200 to bits so I'm struggling to remember that sort of detail. From looking at JefUK's 'Replacing the Humax PVR-9200T Clock Module' document I can see the lower lugs are shouldered and must clip into place, I'm guessing the shoulders align around lugs on the chassis. I can only suggest that you look carefully at what you are doing and don't force anything. I don't remember having any difficulty so I don't think there's any secret.

My board is still working with no further cleaning.

How about if the board is re-lacquered ?

Probably won't do any harm provided the board is properly cleaned and a PCB lacquer is used. Martin's response above suggests it's not necessary though, the board shouldn't need much protection from a living room environment.

Thanks for your 'behind the scenes' message, I was on holiday at the time and am slowly catching up. I have no idea what the contaminant is but assume it is a deterioration and subsequent chemical reaction of the protective lacquer used during manufacture, or some other compound left behind. There is no need to go mad cleaning the whole board, although I detected the problem all over the board the only components affected are in the area I describe in my first post.

Mine still works fine, thanks for the fix.

Another success for Big-Les. I gave mine a good sluicing about a week ago - haven't missed a recording since then. The display is barely visible on the 9200 but it's on the screen.I used ISOPROPANOL with a paint brush (cotton buds were messy). What a difference between the help one gets from an enthusiast and what one gets from -SUPPOSED - help desks.I recently asked Philips re one of their products - the help desk said they had never heard of it!
Last edited by gabljabr : 14-07-2012 at 12:10

My display is quite dim but as I mostly use the 9200 in the evening it's not a great problem for me. I run my Panasonic machine display dim as well and the two look fairly similar.

I would have used isopropanol if the bottle hadn't been empty.

Took my box apart, visible residue around the crystal and capacitor connections. Cleaned it all up with surgical spirits and the clock has returned! Thanks Big Les.

You're welcome.

It was last year 10th September that I cleaned my circuit board and yesterday the clock problem returned.
I read that I may have missed contamination last time I did the clean but I was very thorough.

Will give it another go when time allows. I notice that a switch off and on of the mains power returns the clock but it is lost again when the unit enters standby.

J

Let me know the result of further cleaning. A few months ago I did check with the owners of the two boards I repaired and they were both still working.

OK - I have cleaned the board again using the recommended method and RS Components 513-679 cleaning fluid which is isopropyl alcohol as previously reported in my post #183.

I gave the board super extra attention and cleaned it three times with cotton buds and a v. small paintbrush. There was no visible residue.

I am allowing any traces of the cleaner to evaporate before re-intalling the Hummy.

Will report back with test results.

J

I set up 5 test recordings and all completed correctly. Each test had time in between so as to force the Hummy to go into standby.
So all is looking well at the moment. Real test is tonight with various reservations.
Regards,
J

The only test you need to do is 'is the clock showing correctly in STANDBY'. If it is then timer recordings from STANDBY will work, short of any other problems. Glad you're up and running again.

Another success! Maplins spray PCB cleaner (£3.99) and a few cotton buds did the job.

Thanks Big Les

All is well with the clock 4 days after the second cleaning.

Thanks again Big Les.
J

Another thank you to Big Les!

First time I tried the cleaning earlier this week I went from an intermittent clock problem to the permanent loss of clock in standby (to --:--), which was a bit of a downer! But I realised that what I'd cleaned clearly had an impact on the issue (albeit negative first time).

Yesterday, I had another more thorough go at it following Les' instructions carefully - and using a brush as well as cotton buds this time to really get in and under components (and Boots Surgical Spirit). Dried it off with a warm hairdryer, too, before re-assembly to make sure it was thoroughly dry (which I didn't do first time). Booted it up, and success!

A couple of thoughts for anyone thinking of trying it:

i) It's easier than you think when you get it opened up - even for a non-techie. But look at the post with the pictures of the components first - it will help a lot.
ii) Be patient and clean thoroughly and slowly both sides of the clock board - as per instructions
iii) If it doesn't work first time, don't give up, but open up and have another go having re-read where Les says to focus the cleaning

I can add a little more to the solution - Vodka works well! If you are careful, you don't need to disconnect the main ribbon cable from the display, only the 4-wire plug from the m/board - which is easy.
Remove the clock pwb fixing screws and manipulate the board on the ribbon to gain access to both sides to clean the surface. Vodka and cotton buds worked. There was no obvious dirt coming off the board, but after careful cleaning, the clock function is now working and so is the 'record from stand-by'

Thanks again, Big-les.