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jurb6006@gmail.com: Feb 23 08:29PM -0800 I got the manual for the 690 or something. The mech is the same but the board is not. I am pretty sure it is an electronic problem at this point. The IC that handles this is IC 501 on the print and IC 201 on the board.   Any ideas at all on where to get the print for this particular board, or possibly an equivalent model ? System control is all I need, everything else seems to be fine.

N_Cook <diverse@tcp.co.uk>: Feb 24 01:26PM > I got the manual for the 690 or something. The mech is the same but the board is not. I am pretty sure it is an electronic problem at this point. The IC that handles this is IC 501 on the print and IC 201 on the board.   > Any ideas at all on where to get the print for this particular board, or possibly an equivalent model ? System control is all I need, everything else seems to be fine.   All the years repairing VCRs, perhaps 200 units or so, I think only 2 were electronics problems, 1 a CCD display driver chip problem, and another a large BGA chip problem that needed a push. Are there indexing marks/arrows etc in the mechanism , in case its jumped a tooth?

jurb6006@gmail.com: Feb 24 06:38AM -0800 >"Are there indexing marks/arrows etc in the mechanism , in case its jumped a tooth? "   There are some. You have to figure it out though because in the manual there is no picture depicting "Setting condition" which shows you how to put it for reassembly. I got it pretty much figured out because I have a guinea pig, another VCR that is nearly identical. The goat...   I took the goat apart and found that the mode switch is full of nice grease and it is not even dirty, and it was treated much worse than the deck I want to fix. All the grease is good, and mind you this 780 works sometimes, it's just that after it warms up and/or goes through a few cycles it does this shit, and displays a bunch of different errors, most of which come back to either it cannot tell what state the mech is in or the unloading is incomplete. I have tested the mode switch with an ohmmeter and it is either a dead short or open depending on the position and which terminals you check. When it works it does not try to overrun the loading motor or anything of the sort.   The fact that it works sometimes leads me to believe the mech is fine. I started to try to trace the mode switch connections back to the IC but the double sided (or more) PC board makes that impossible. In fact it is more than two layers because the traces from the mode switch go to vias and then on the other side is solid copper, a ground obviously. there must be at least one more layer in between.   The print depicts IC 501 and on the board is IC 201. That is where the difference starts. The board.   I probably posted prematurely, I was going to somehow check the end sensors because they are involved in the loading process. But last night I decided to putz around with it and find the place where the mode switch actually gets to the IC. I'll need to test it on the actual deck I am fixing because the goat is all apart, and I found out that little plastic things break when you remove the mode switch. So I am treading lightly because I know most of theparts are unobtainium. And if it is the IC, not only do I not have the proper equipment to change it, I don't have it to get the replacement out of the goat, and plus it has the same problem,or at least it was found in the same state, tape stuck etc.   I might have to just say fukit and fix the 920, now that one IS dried grease. I have not worked on one but I am familiar enough to know the the grease on the one tape arm dries up and it strips the rack gear. Yes, one of those. So I intend to address that before even plugging it in. I got LPS2 which is so good it will do it without disassembly, but I would rather do it right, get all that goop out. The grease in the 740 (the goat for the 780) is in such good shape maybe I should use that.

Terry Schwartz <tschw10117@aol.com>: Feb 24 07:02AM -0800 Printed circuit boards are always composed of layer pairs. So there must be at least *two* layers in between.

"Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com>: Feb 23 10:42PM -0500 I just twisted a torx bit into a spiral trying to remove a rusted screw, then used a Dremel to cut a slot across the top and took it out with a flat screwdriver. The screwdriver didn't bend at all.   None of the bits I ever saw are made of hardened steel like a single-piece screwdriver. Does anybody make harder bits?   --

"Tim Williams" <tiwill@seventransistorlabs.com>: Feb 23 11:25PM -0600 Where did you get the poor things?   The cheap box of bits I got from Horrible Freight, I'd be rather more concerned that they're going to snap into pieces if I force them hard.   I've bent and twisted dozens of screwdrivers, though.   Tim   -- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design Website: https://www.seventransistorlabs.com/   "Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com> wrote in message news:p6qqqs$cev$1@dont-email.me...

oldschool@tubes.com: Feb 23 11:34PM -0600 On Fri, 23 Feb 2018 22:42:47 -0500, "Tom Del Rosso" >flat screwdriver. The screwdriver didn't bend at all.   >None of the bits I ever saw are made of hardened steel like a >single-piece screwdriver. Does anybody make harder bits?   Put some Viagra tablets in the container where you keep your bits. They will get hard! :)

Paul in Houston TX <Paul@Houston.Texas>: Feb 23 11:41PM -0600 Tom Del Rosso wrote: > flat screwdriver. The screwdriver didn't bend at all.   > None of the bits I ever saw are made of hardened steel like a > single-piece screwdriver. Does anybody make harder bits?   Snap-On and Proto both make good torx bits. $12 per bit. They don't bend, they just suddenly break.

kludge@panix.com (Scott Dorsey): Feb 24 08:22AM -0500 >flat screwdriver. The screwdriver didn't bend at all.   >None of the bits I ever saw are made of hardened steel like a >single-piece screwdriver. Does anybody make harder bits?   Proto and Mac do, I think PB Baumann does also. They aren't cheap, but they work. We use the Proto ones.   In addition you may want to invest in some Kroil or PB Blaster, and maybe a small torch.... --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."

FreeMan <freeMan@SpamFree.com>: Feb 24 06:05AM -0800 Don't forget they have a lifetime warranty on hand tools so get a better replacement.     Tim Williams wrote:

N_Cook <diverse@tcp.co.uk>: Feb 24 01:21PM Every now and then resets to some sort of default, 01 01 2005 data and Tokyo radio system , so never resets to local time codes. Have to then reset it manually. No problem suggesting a low battery or any other timekeeping problem. I've tried holding down various buttons to check if its due to bad switch contacts but never induces this default.

"pfjw@aol.com" <pfjw@aol.com>: Feb 24 05:25AM -0800 There will be a memory-keeping capacitor in there somewhere that is going either faulty (age) or intermittent (cold solder). Either way, replacing it will fix it.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Feb 24 01:37PM > There will be a memory-keeping capacitor in there somewhere that is going either faulty (age) or intermittent (cold solder). Either way, replacing it will fix it.   > Peter Wieck > Melrose Park, PA   I'll bear that in mind, if I have to go inside. At the moment I'll go with the business about button-D on this thread http://webcache.googleusercontent.com/search?q=cache:gk35QWiIPaEJ:http://www.fixya.com/support/t2294665-reset_itslelf_will_not_display_correct%2BCasio+Wave+Ceptor+radio+controlled+watch,+WR50M,+resets+to+2005+tokyo+default&hl=en-GB&gbv=1&ct=clnk   I'll snap back a sewing-pin , after pushing it into the D button to wedge it out, and swathe in a dot of hotmelt glue. Resetting the thing , before doing so , of course

oldschool@tubes.com: Feb 24 12:50AM -0600 Do they sell a gauge to measure Coaxial Power Connectors? AKA "barrel connectors".   I can get close using a ruler on the outer part of the plug, but those pins inside are near impossible to measure.   There are so many variations of them too.   Someone must have some sort of gauge to measure them....

Mike Coon <gravity@mjcoon.plus.com>: Feb 24 08:25AM In article <ik229dl060m7ifsdpnlubj9oa1i3norutr@4ax.com>, oldschool@tubes.com says... > pins inside are near impossible to measure.   > There are so many variations of them too.   > Someone must have some sort of gauge to measure them....   Sort of. I either use one of a set of matching sockets or small lengths of fine tubing. Sockets are easier to measure using fine twist drills which are typically sold in sets...   Mike.

tabbypurr@gmail.com: Feb 24 12:44AM -0800 On Saturday, 24 February 2018 08:25:21 UTC, Mike Coon wrote: > of fine tubing. Sockets are easier to measure using fine twist drills > which are typically sold in sets...   > Mike.   outer dia: micrometer, drill bits, nails inner dia: drill bits, small nails/pins,     NT

"Gareth Magennis" <soundserviceleeds@outlook.com>: Feb 23 07:28PM "Phil Allison" wrote in message news:2750eec0-a130-4e4b-8b69-9a69ca1edb1b@googlegroups.com...   Gareth Magennis wrote:   -----------------------   > Well a piece of wire worked a treat.   > With a bit of heatshrink for strain relief at the transmitter end and > another on the end of the tail, it even looks like a proper one.   ** So now you know how to make a "rat tail" antenna.     > Thanks to all for the calculations and info.     ** 300 / MHz = wavelength in metres, is worth remembering.     FYI:   That AG-1 unit is about as basic as UHF FM links get, so has limited useful range and is prone to signal drops out due to multipath interference. The Tx signal can almost cancel itself after reflecting off objects and surfaces and then arriving at the Rx.   Better models have twin channel receivers, with two separated antennas, operating as a diversity pair that helps greatly to eliminate such drop outs.       .... Phil       ******************************************     Presumably the transmitter antenna should be straight for best efficiency.   If it is (worst case scenario) a semicircle, what changes?     Gareth.

Phil Allison <pallison49@gmail.com>: Feb 23 03:04PM -0800 Gareth Magennis wrote:   -----------------------   > Presumably the transmitter antenna should be straight for best efficiency.   > If it is (worst case scenario) a semicircle, what changes?   ** Every effort should be made to straighten it !   It's an FM signal, so the recovered audio is not affected until the RF level becomes very weak. Meaning there is usually plenty in reserve to allow for circumstances that reduce the RF level compared to free field.   Players buy units like this not to get long range, but merely to be free of that damn instrument cable.     .... Phil

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Feb 23 06:40PM +0100 On 23-2-2018 16:22, JBI wrote: > is coming from the inverter, so how would I negate it? I've tried about > 5 snap closed ferrite cores around the power cable going into the laptop > but they haven't helped. Thanks.   A differential amp, to get rid of a ground loop.   Or feed both devices from the same minus 12v point.   Or both.

Tim R <timothy42b@aol.com>: Feb 23 10:38AM -0800 You've tried it with good headphones, right?

Jeff Layman <jmlayman@invalid.invalid>: Feb 23 07:06PM On 23/02/18 15:22, JBI wrote: > is coming from the inverter, so how would I negate it? I've tried about > 5 snap closed ferrite cores around the power cable going into the laptop > but they haven't helped. Thanks.   Have you considered using a direct supply with an input of 12v and output to suit most laptops (19V? You didn't say which make you have). Typical example here, but many others available at all sorts of prices and quality: <https://www.ebay.com/itm/Universal-DC-15-24V-Car-Auto-Charger-Adapter-Power-Supply-for-Laptop-Notebook-PC/191191789071?epid=560493099&hash=item2c83eb2e0f:g:FEwAAMXQ1ZhThFqB>   Hopefully, although also a SMPS it will not produce the sort of interference you are getting from your 12/120V inverter.   --   Jeff

Terry Schwartz <tschw10117@aol.com>: Feb 23 12:45PM -0800 On Friday, February 23, 2018 at 9:22:38 AM UTC-6, JBI wrote: > is coming from the inverter, so how would I negate it? I've tried about > 5 snap closed ferrite cores around the power cable going into the laptop > but they haven't helped. Thanks.   Get rid of the inverter. They are all horrendous noise sources. Run on battery.

"Gareth Magennis" <soundserviceleeds@outlook.com>: Feb 23 10:10PM "JBI" wrote in message news:p6pbjo$kkr$1@dont-email.me...   I am using a standard 400 W 12 VDC to 120 VAC inverter to power my laptop in the car. While this works well, lately I've started doing audio work with the laptop and feeding the laptop 1/8" audio jack output into an amp hooked into the car radio. While the laptop is plugged into the inverter, I get much noise over the audio system. I know the noise is coming from the inverter, so how would I negate it? I've tried about 5 snap closed ferrite cores around the power cable going into the laptop but they haven't helped. Thanks.       *****************************     Well the best bet is to use the laptop battery when noise is critical.       Gareth.

"Ian Field" <gangprobing.alien1@virginmedia.com>: Feb 23 09:11PM "Bruce Esquibel" <bje@ripco.com> wrote in message news:p6p17o$rr2$1@remote5bge0.ripco.com... > need is a computer with iTunes running on it, put the device into the DFU > mode (google it) and restore as a new device.   > That'll erase everything on it but it'll still be useable as a new device.     Thanks.

etpm@whidbey.com: Feb 23 09:09AM -0800 On Thu, 22 Feb 2018 10:53:47 -0600, Fox's Mercantile <jdangus@att.net> wrote:   >> There is an ozone filter in it they say.   >The manual says it generates ionized air. >That by definition is ozone Last I heard ions are atoms that have either a net positive or net negative charge. Meaning there are not an equal number of elctrons and protons. Ozone is just a molecule, O3. The most common oxygen molecule is, of course, O2. Either molecule can be ionized though. Eric

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