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"Ian Field" <gangprobing.alien@ntlworld.com>: Oct 18 04:40PM +0100 "Phil Allison" <pallison49@gmail.com> wrote in message news:0b2eab1a-cf45-4175-81cb-ad390b3fad95@googlegroups.com... > touch on the feed handle. There are 5 or 6 holes that need doing at both > ends.   > The cast alloy was a bit too hard for a drill bit held in the fingers.   Usually I find cast alloy heatsinks in automotive assemblies and power tools, they seem to be the exception in most other things.   The common rolled sheet aluminium is very easy to cut too deep, I think extruded is a little harder, but it still needs a light touch if you do it in a drill press.   Anything other than a block can also snag on the drill bit if you accidentally go right through.

Mike Tomlinson <mike@jasper.org.uk>: Oct 18 10:12AM +0100 En el artículo <b95c6698-781d-4f89-bebe-46693a690215@googlegroups.com>,   >el valor de r602 es 22 ohms a 1w   felicidades por responder a un mensaje de 18 años de edad!   -- (\_/) (='.'=) Bunny says: Windows 10? Nein danke! (")_(")

mroberds@att.net: Oct 18 09:11AM > Or, are there switch-boxes available as an alternate solution, where > you manually can switch from one HDMI source to another one, and then > feed the single TV HDMI Port ?   You can get these, but get a switch box that has its own power source, and doesn't try to derive power from the HDMI port on the TV.   HDMI does have a power wire but the power available is really low - less than USB, if I remember right. It's not really enough to run much of any external hardware.   I have used a totally electromechanical HDMI switch box on a Toshiba TV and couldn't get it to work right.   HDMI also has a handshake that has to happen; sometimes the TV will sync back up after you operate the switch box and sometimes not. You may have to power-cycle the TV or the HDMI source device after using the switch box, to get a picture.   Matt Roberds

"Michael A. Terrell" <mike.terrell@earthlink.net>: Oct 17 08:00PM -0400 Phil Hobbs wrote:   > > http://jimmyauw.com/2015/03/01/hp-agilent-3561a-dynamic-signal-analyzer/   > And if not, I posted it here:   > http://electrooptical.net/www/sed/HP3561A_ServiceManual.pdf       <http://www.keysight.com/main/techSupport.jspx?searchT=3561A&id=3561A:epsg:pro&pageMode=OV&pid=3561A:epsg:pro&cc=US&lc=eng>   has both the service and the operating maunuals. Keysight it the latest name change for HP test equipment.

jurb6006@gmail.com: Oct 17 08:47PM -0700 They actually do not have volume two of the service manual. We just got it, ON PAPER. Quite illustrating. The unit is up and running again with the replacement of a 7912. Apparently my shenanegins made leaky the device inside there.   I am back to the vertical sweep problem now. I'll probably get back into it next weekend. Give it some thought in the meantime.

"David Farber" <farberbear.unspam@aol.com>: Oct 17 03:59PM -0700 A while ago I started this thread about an HP DV9000 laptop that had no video. https://tinyurl.com/ndtmko6   The follow up to that story is I sent the board out for repair. Nearly two months later, I got it back. I reinstalled it and it worked fine....for two days. Then the video went dark again. I decided the best thing to do was to order a brand new board and not have to deal with intermittent, old, connections causing me grief. Now the situation is, as is with many of these HP boards, how do I keep the processors cool to prevent a reoccurrence of the problem?   Here are some pictures: http://webpages.charter.net/mrfixiter/images/Electronics/DV9000/cpu-northbridge.jpg   http://webpages.charter.net/mrfixiter/images/Electronics/DV9000/GPU-shim.jpg   Let's begin with the biggest concern. In the first photo, there is an extra piece of copper that extends downward toward the motherboard. It's labeled, "Northbridge 1.5mm gap." That is approximately how much space there is between the copper and the Northbridge chip when the heat sinks are installed. On the old motherboard, that gap was filled with a spongy thermal pad. The consensus is that if there were an uninterrupted piece of copper between the heat sink and the chip, the cooling would be much more efficient. By the way, what is that stuff that can be peeled off? Would that just be regular electrical tape?   Here is a good video showing the orientation of the components. https://www.youtube.com/watch?v=t9w-khwIj3U I'm not sure I would stick a penny under the heatsink to fill in the gap but that's what this particular user did. The other thing I don't understand from the video is why are shims inserted under the CPU and GPU if they already come in contact with the heat sink?   In the second photo I linked, you can see the heat sink for the GPU. There is black tape attached to the heat sink. Does that help dissipate the heat? Is that there for electrical insulation? Finally, the motherboard came shipped with a "bonus" copper shim. It's too thin to help with the gap in the Northbridge chip. Referring back to the video, the user put one shim under the CPU, and another one under the GPU. I decided to put the one shim I received under the GPU since that seemed to be the cause of the failure. What makes more sense to me is to fill in the Northbridge gap with copper shims (is it ok to stack them if I can't measure the exact thickness before I buy them?) and leave the CPU and GPU as is. What do you think about this?   Thanks for your replies. -- David Farber Los Osos, CA

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