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W Pulaska <nsd@nda.net>: Jun 13 09:23AM -0400 Pretty simple set up. I have my phono output from my desktop Audiofile 2496 sound card driving an Altec Lansing speaker set. Works fine when everything is on, but when the desktop is turned off I am getting a buzz/ hum from the speakers and loud enough that I power them off. Why is this and how to remedy? Thanks.

legg <legg@nospam.magma.ca>: Jun 13 09:42AM -0400 >everything is on, but when the desktop is turned off I am getting a >buzz/ hum from the speakers and loud enough that I power them off. Why >is this and how to remedy? Thanks.   I think your desk-top has a soft and a hard power switch. There may also be other peripherals that are still running plugged into the desktop.   If the humming is still there when the hard power switch is off, try terminating the signal lines from the PC with 600R. The PC may go high-Z when turned off - becoming a hum antenna.   Fool with cables to see if any movement modulates the amplitude.   Check grounding on the PA - are these active loudpeakers?   The source volume should be high, the amplifier's gain low, for best S/N performance.   RL

bje@ripco.com: Jun 12 05:16PM > of power. Therefore, there was NO need for a battery (does NOT have one).   > After the VCR failed to record at the appointed time, the time and date > was checked and was correct.   Doesn't matter.   If it does have some kind of power backup device, either battery or supercap, after 35+ years it's probably chemically broken down and is likley holding one of the lines to the cpu low.   You might think you are programming a record event but the cpu is ignoring it.   If you are absolutely sure there is no such device, take my other suggestion and go visit the nearest Salvation Army or Goodwill outlet store.   There are two of those on ebay now, one for $12.50 and the other for $20 (or best offer) but of course there is $20 in shipping charges on either.   Overpriced.   Assuming everything else is working correctly and it is just a timer problem, it's so unlikely to find a replacement clock/timer board these days and probably priced at 10x what the machine is worth, there really is no other solution except to replace the whole machine.   -bruce bje@ripco.com

jaugustine@verizon.net: Jun 13 08:28AM -0400 >problem, it's so unlikely to find a replacement clock/timer board these days >and probably priced at 10x what the machine is worth, there really is no >other solution except to replace the whole machine.   Hi Bruce,   Since I do not have the SM for this, and I have other VCRs that I can use for Timer Recording, I will only use this VCR without the Timer Recoding function.   Regards, John

T i m <news@spaced.me.uk>: Jun 13 11:24AM +0100 On Fri, 11 Jun 2021 21:52:09 +0000 (UTC), Akakios Peretz   >T i m <news@spaced.me.uk> wrote: >[text with no question snipped]   >And the question you wanted to ask the group was what???   Erm ... apart from in the message header I thought it might have been sufficient here:   "Having a tidy up in the study yesterday I took the top of my old Davtrend 13.5V 12A 'shack' PSU (used to power my Packet Radio station) and gave it a gentle dust out and felt I'd like a circuit diagram for it."   Ok, I'll rephrase it then. ;-)   Can anyone point me to a link to a circuit diagram for a Davtrend CL-19 please?   Cheers, T i m

John Robertson <spam@flippers.com>: Jun 12 02:57PM -0700 > Zerox (ok, it was Savin then) copy of the service manual, but it says nothing > about this. Yeah, it's nostalgia and prolly not worth the effort. But would > appreciate any tips from anyone who has done anything like this before.   I have not done the process, however I do advise you wear protective clothing (heavy leather/armoured apron or jacket and gloves) and a full face shield that protects your eyes and neck when working with picture tubes. They can be very dangerous, in close quarters, if broken...   John :-#(# -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Michael Trew <mt999999@ymail.com>: Jun 13 12:10AM -0400 > Zerox (ok, it was Savin then) copy of the service manual, but it says nothing > about this. Yeah, it's nostalgia and prolly not worth the effort. But would > appreciate any tips from anyone who has done anything like this before.   Would that be anything like the CRT "cataracts" that tend to plague older CRTs? I've seen this type of issue clean back to post-war televisions, possibly earlier. I've seen some that look different from others.   https://www.youtube.com/watch?v=4zKnRoNc9Q0

Stephen Wolstenholme <steve@easynn.com>: Jun 13 10:37AM +0100 On Sat, 12 Jun 2021 14:57:57 -0700, John Robertson <spam@flippers.com> wrote:   >face shield that protects your eyes and neck when working with picture >tubes. They can be very dangerous, in close quarters, if broken...   >John :-#(#   I worked on a TV production line for a few years. Nobody had protective clothing. Just occasionally a CRT would implode when it was lifted out of the delivery box. It was seen as a loss of production time rather than a potential injury.   Steve -- http://www.npsnn.com

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