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Tom Kupp <tjkupp@gmail.com>: Sep 18 10:34AM -0400 I've had this for a long time, but haven't used it for 5 years. Somehow the ac adapter and whatever literature there was have disappeared. Can anybody tell me the DC voltage and current specs?

danny burstein <dannyb@panix.com>: Sep 18 03:53PM >I've had this for a long time, but haven't used it for 5 years. Somehow >the ac adapter and whatever literature there was have disappeared. Can >anybody tell me the DC voltage and current specs?   There's a realistic chance that if you get out a magnifying glass and hold the unit at an angle to the light, that you'll see, in teensy raised print, the numbers you're looking for.     -- _____________________________________________________ Knowledge may be power, but communications is the key dannyb@panix.com [to foil spammers, my address has been double rot-13 encoded]

Tom Kupp <tjkupp@gmail.com>: Sep 22 10:22AM -0400 On 09/18/20 11:53, danny burstein wrote: > a magnifying glass and hold the unit at an angle > to the light, that you'll see, in teensy raised > print, the numbers you're looking for.   No joy, just says POWER.

Tom Kupp <tjkupp@gmail.com>: Sep 27 11:38AM -0400 > Submit a question. Can't hurt, might help. Otherwise, back into what is needed as others have advised.   > Peter Wieck > Melrose Park, PA   Thanks; I have submitted a question.

crazy chicken <craziestchicken2007@gmail.com>: Sep 25 07:02PM -0700 I am having the exact same problem. What is broken, the VCR or VHS that is making it B&W. Is everything B&W because my VHS tapes are too old and have eroded? I have tapes since 1990, so do they still work 30 years later? Is there no solution to this problem? I am trying to get my tapes to digital, and I need to solve this problem. Thanks for reading! - A Chicken

dplatt@coop.radagast.org (Dave Platt): Sep 25 09:54PM -0700 In article <0e80f69b-170d-4252-9982-7405105d3484n@googlegroups.com>, >because my VHS tapes are too old and have eroded? I have tapes since 1990, so do they still work 30 years >later? Is there no solution to this problem? I am trying to get my tapes to digital, and I need to solve this >problem.   https://www.broadcaststore.com/pdf/model/793700/TT198%20-%204802.pdf has some useful information about how VHS color recording works, although the details of the testing procedure it suggests won't help you all that much.   With tapes in good condition, and a VCR in good condition and alignment, color playback should work OK. It's unlikely that several different tapes would have degraded in the same way, so the fault is more probably with the VCR.   VHS can lose color because of dirty or bad playback heads in the drum, or because of a fault in the color-conversion circuits (VHS stores the color information in a different frequency band than is used by NTSC video). A failed 3.68 MHz color-reference oscillator would be one such possible fault, and I'm sure there are plenty of others.   Sure, there's a solution: try a different VCR, preferably one which is in known-good condition.   Your existing VCR might be repairable; it might need something as simple as a good professional cleaning (and I don't mean a "cleaning tape", I mean a by-hand cleaning by a technician who knows how to do it properly and who won't damage the heads) or it might need circuitry repairs. Old VHS players are common enough that simply buying a (used) replacement is likely to be cheaper than a repair.   Another possibility - if you have hooked your VCR up to a TV/monitor using an S-video cable, try a different cable. S-Video sends the luminance (brightness) signal on one wire, and the chroma (color) signal on another wire. A broken wire or pin could cut off the chroma and leave you seeing black-and-white. See if the problem is still there if you use a composite-video cable (RCA plug/jack, usually yellow) rather than S-Video.   If you're trying to video-capture onto a PC, you might have a problem with your video-capture card.

amdx <amdx@knology.net>: Sep 25 01:00PM -0500 On 9/25/2020 10:50 AM, Jeff Liebermann wrote: > <http://www.ambery.com/rfmp-w50.html> > Dimension: 498mm (W) x 360mm (D) x 280mm (H) > Or, perhaps you mean't something other than size?    I stored a rack mount Wingard distribution amplifier for years before I tossed it.   I was about 19" x 6" x 3".   I always thought it would be good for something, but never ran across that something.                                            Mikek               -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Ron D." <ron.dozier@gmail.com>: Sep 25 12:36PM -0700 jeff:   Antenna is pretty big, A Winegard HD-8200U and the CM-7777 antenna mounted amp.   The reason why I don;t TRUST is I did gain measurements using a Sencore 8VSB tester. My gain measurements were not consistant, but they were not done at the same time. I measures the signal at the antenna and the NEXT day the signal after the power injector (about 30')   Gain varied from 15.6 (physical channel 3) and 27.1 for channel 21. I'm at least 30 miles outside of Philly and aimed toward Philly stations.   The rotor also has a bypass braid around it which many people forget. A large tree is going to hit by lightning first.

David Farber <farberbear.unspam@aol.com>: Sep 20 03:36PM -0700 This Carvin B2000 bass amplifier was brought to me with the problem that it wouldn't turn on. The user said it was working fine until there was a bright flash that could be seen through the front grill. Then it went dead. I opened it up and found a very fried and crispy looking disc which I think is an MOV. It's labeled TR1 on the "main board close up" as seen in these pictures. You can see by the photo it parallels the (removed) relay's normally open contact (AC out?) and the common, AC in contact. Photos are here, https://app.box.com/s/ch670hnsrtoswqhebtrye95n2vw5ktre   The other photos are to give you a general idea of what the board looks like. The reason I took photos of the entire board is that Carvin's own website, https://carvinaudio.com/pages/bass-amp-schematics shows different versions of the B2000 schematic but none of them matches what I see in the version I'm trying to troubleshoot. There is one vacuum tube in the unit, a 12AX7.   After cutting out the MOV, and then powering it up, the power relays would not engage. The other issue is that when I pulled out one of the two power relays for inspection of its discolored contacts after it failed to power up, one of the pins came out of its coil. There is no writing on the relay and its physical construction doesn't look at all familiar to any relays I've ever seen. I need to replace it assuming the unit is worth fixing.   Does anyone have a schematic for this amp? There is a description of the amp here: https://carvinaudio.com/pages/archive-carvin-b2000-lightweight-mono-block-2050w-bass-amp-head   The owner said it was purchased around 2000. It looks in good shape for being 20 years old. According to this report, https://www.thetonerooms.com/threads/carvin-amps-out-of-business.3035/ Carvin went of business in 2017.   Thanks for your replies. -- David Farber Los Osos, CA

David Farber <farberbear.unspam@aol.com>: Sep 20 10:17PM -0700 On 9/20/2020 8:06 PM, Phil Allison wrote:   Hi Phil. I think I'll try using one of my audio, 8 ohm, 25 watt dummy load resistors to test it. I'll also put a 200 watt light bulb in series with the Variac just in case. If there's no overload, then I may as well pull out the other identical inrush relay and see if I can figure out what voltage and current it takes to close the contacts. Any idea what voltage and current rating those contacts need to be?   Thanks for your reply. -- David Farber Los Osos, CA

legg <legg@nospam.magma.ca>: Sep 21 09:46AM -0400 On Sun, 20 Sep 2020 22:17:29 -0700, David Farber >pull out the other identical inrush relay and see if I can figure out >what voltage and current it takes to close the contacts. Any idea what >voltage and current rating those contacts need to be?   It's a fairly common form used in HVAC switching, but more easily obtained with a plastic dust cap. The open air parts are seldom used outside of self enclosed fan-free environments, for obvious reasons.   You may have a relay on both input (inrush limiting) and output (click and pop supression).   You'll need to establish what the supply voltage is for the coils.   Check for Panasonic JTV or TEconnect T9AS1D series SPST NO.   RL

Peabody <waybackNO584SPAM44@yahoo.com>: Sep 20 03:54PM -0500 > to replace (except you'll have to identify them, and > match to modern available parts, and pay shipping for > onesies...).   I removed all of the electrolytics, and all but one tested good on my scope. I replaced the dubious one, but the flash still doesn't work. The oscillator whine doesn't start up.   But I did find one thing that gets really hot when the power switch is turned on. It is a pair of three-pin parts (triange pattern footprint) that look like cylinders, and they are enclsed in a U-shaped heatsink. They are each marked with the Mitsubishi triagle logo, and "B324ST", with "12" on the second line. I assume they are transistors or thyristors, but searching for them comes up with nothing. This is all from the 1980s, so I guess it's not surprising that the parts aren't active anymore, but it would be nice to at least find a datasheet.   By the way, the dubious cap was right next to the mystery pair.   Any ideas?   https://www.eevblog.com/forum/repair/repair-vivitar-3500-speedlight/? action=dlattach;attach=1070818;image

Peabody <waybackNO584SPAM44@yahoo.com>: Sep 20 04:06PM -0500 Someone on the EEVblog forum says the part number is actually 2SB324, which is a germanium PNP transistor. I'd guess I won't find a direct replacement for that.

Bradley Bowman <bradleybowman89@gmail.com>: Sep 19 12:03AM Hi guys, first time posting to a newsgroup, been lurking for a few weeks though.   I'm attempting to repair a Bose Acoustimass 9 for a customer; I'd already fixed the display on his LifeStyle 5 CD player and the amp in the subwoofer appears non- working. I tested the sub with a signal generator, and the satellite speakers as well, so I've got the power board, the (rather large) transformer, and the main amp board to mess with.   I've found the 10-page schematic for this system via a Google search, but the Bose manual for the LifeStyle 5 system was very informative, wondering if anybody has the one for the Acoustimass amp portion?   Thanks, Brad

JC <Chipbee40_SpamNo@yahoo.com>: Sep 17 02:05PM -0400 > This helps a little. > thank you very much!   Translation in case you need it:   https://flic.kr/p/2jHx61m

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