PM3065 long term, things to worry about? - Page 1
Forum section: electronics / testgear

author: TinkerFan
author_rank: Regular Contributor
timestamp: January 09, 2016, 10:16:40 pm
content: Hi all,I got a PM3065 100MHz delayed time base scope last summer and i'm a bit worried about several things:First, the frontend:It has a LCD and instead of knobs buttons to change time base, voltage etc. All this is controlled by a 8052 micro via the I²C bus. Now, I'm a bit worried, that the processor dies, and the scope becomes (almost) useless, because the whole frontend isn't working anymore. Is there anyone, who has the code, or would it make sense to ask Philips (or were they also bought by someone? - as everyone...), if they still have the code or any kind of replacement? Is it even worth searching for it, or are the things stable enough?The trigger level control:It seems to work, but it can only move over about half (or less) of the amplitude. I'm not very familiar with analog scopes, but that seems a bit less to me. It seems to that a special IC handles all that trig level stuff, and I wasn't able to find an adjustment pot or so. Have I overlooked something?Other things that can go pop or boom...Apart from caps, is there anyone, who has (had) issues with this scope, or are there other common failures or custom chips, which should worry me?All that might seem a bit too careful and strange, but 200€ is a lot of money for a student, and I do not want to buy a new scope in 2 years...GreetingsPS: The User manual and the schematics:User manual/advert with specs:http://www.test-italy.com/Specifiche%20strumenti/PHILIPS/PHILIPS%20PM%203055/PM%203055.pdfAnd schematics:http://bee.mif.pg.gda.pl/ciasteczkowypotwor/Philips/pm3065%20pm3067.pdf

author: Kleinstein
author_rank: Super Contributor
timestamp: January 09, 2016, 10:52:09 pm
content: With many modern instruments there are special chips that are hard or impossible to replace. I don´t think 8052 µC are very prone to failure - so I won't worry that much about it.Some of the older 100 MHz scopes might have custom chips / hybrids in the input section and the output amplifier. These would be the bigger concern in old scopes. I don't know if phillips uses them. These are e especially a problem with high temperatures or at high altitude (poor cooling).There is a small risk with any type of elektronics: The old scope but it has lasted for 20 years or so - why not another 10.

author: Shock
author_rank: Super Contributor
timestamp: January 10, 2016, 05:44:34 am
content: I have two PM3065 with original probes and manuals and another spare parts unit. The problematic parts I've come across are:X2 cap shorts rather badly from age (power pcb)Reservoir and filter caps fail from age (power pcb)Potentiometer nylon shafts get fragile and break (front pcbs)D7004 death causing loss of x1 x10 scaling (front pcb)LCD dies most likely from knock or drop damageLCD back-lighting fails from age200€ you paid similar to what I paid for my 3 all together a few years back. I think you will find it's pretty common for people to have a few of each unit, brought when they were cheap so they have spares if they need them.

author: TinkerFan
author_rank: Regular Contributor
timestamp: January 10, 2016, 01:11:33 pm
content: Thanks for the replies, but there is still the problem with the trig level control, is there a way to fix that? I wasn't able to find a trimmer for that purpose, but I might have overlooked something.Quote from: Shock on January 10, 2016, 05:44:34 amThat is really cheap, I've seen them for more than 400$. Were they broken?Thanks for the list of possible failures. D7004 seems to be something custom, is there a datasheet?Quote from: Kleinstein on January 09, 2016, 10:52:09 pmI think this scope has a lot of them, especially in the front end section, due to that I²C bus...Would it make sense to ask Philips, if they still have some information about the chips?

author: Shock
author_rank: Super Contributor
timestamp: January 10, 2016, 03:13:47 pm
content: Quote from: TinkerFan on January 10, 2016, 01:11:33 pmNope but the courier had a good go at trying to break one. I can see the sales history onhttp://www.ebay.deand it looks like they have gone for cheaper. The D7004 won't be a common failure, the X2 cap is a common failure and a burning one.

author: TinkerFan
author_rank: Regular Contributor
timestamp: January 10, 2016, 07:10:50 pm
content: Quote from: Shock on January 10, 2016, 03:13:47 pm've had that problem once and when they die, they release an ugly amount of smoke...

author: karoru
author_rank: Regular Contributor
timestamp: January 12, 2016, 02:05:08 am
content: Quote from: Shock on January 10, 2016, 05:44:34 amBy the way I've seen these scopes (and other Philips scopes from that era) marked also as Philips-Fluke or Fluke, do you have any idea which company actually produced these, and which was a rebranding?

author: Shock
author_rank: Super Contributor
timestamp: January 12, 2016, 03:37:06 am
content: Quote from: karoru on January 12, 2016, 02:05:08 amFluke brought the testing and measuring device division of Philips, you can read about it here:http://www.fundinguniverse.com/company-histories/fluke-corporation-history/