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gregz <zekor@comcast.net>: May 04 07:30AM >> Any tips or suggestions?   >> Thanks in advance.   > **If you care about sound quality, avoid piezos.   How old are these Fishers ?   Newer types are junk anyway. Piezo might be fine if you work out the details as suggested. Your crossover might just be a cap plus possible resistor.   How old are these Fishers ? Model number ?   Greg

Adrian Caspersz <email@here.invalid>: May 04 11:29AM +0100 On 03/05/17 22:25, amdx wrote:   > I used to work in a consumer electronics repair shop. > Authorized repair for about 100 brands, but we made a > lot of money on Fisher products.   I like the build of this Fisher pricey dual cassette deck.   https://www.youtube.com/watch?v=vmPhJj4WDOI   -- Adrian C

tabbypurr@gmail.com: May 04 04:58AM -0700 > are used for).   > Any tips or suggestions?   > Thanks in advance.   Piezos are not the 'junk' some opine, far from it. But they're not top of the tree either. If you're not spending lots of $ then piezos can deliver quite good performance at relatively low price. Their shortcoming is the frequency response is a bit uneven at the top end, but domes, cones etc aren't flat either.   They can be connected where your old tweeters were if you add an 8R resistor - piezos are high impedance devices, at least in their operating range. Always put a series resistor on piezos, 10R is ok. Otherwise the amp sees a capacitive load, and some are not ok with that.   Any type of tweeter comes in good & not so good variants. If I were buying blind (or deaf) for average consumer kit I'd be more likely to get a happy result from piezos than domes.   Crossover frequency is typically 1 - 4kHz. Tweeters only handle somewhere vaguely in the region of 20% of a speaker's input power.     NT

"pfjw@aol.com" <pfjw@aol.com>: May 04 05:59AM -0700 YIKES!   OK - you are running your Altec amp at the 1/3 point. That does NOT mean you are putting 100 watts into the amp.   You really need to learn some of the basics of audio. Little steps for little feet:   a) Audio Taper Controls: https://i.stack.imgur.com/f5P1V.png   At the 1/3 point you are, perhaps, putting 10% of the amp power into the speakers - and that ONLY IF the signal is driving the amp to that level of power. So, maybe 30 watts at the absolutely loudest passage.   b) Amp output vs. signal input: Amps are rated in WPC/RMS (watts-per-channel/root-mean-square), and at a specified voltage input. Typically around 2V or so, typically at a specified frequency or group of frequencies. A preamp varies the level of input into the amp, from 0V up to as much as 13-or-more V. Consider on that and consider why.   c) I do not know what you listen to, in general. Whether it is classical (as in orchestral or 'high-brow' stuff), rock, country, Polka, or whatever. But, *most* music as recorded these days has a Peak-to-Average of 20dB at the high end, to under 10dB at the low end. Very, very few recordings even approach 30dB. So, if you are listening to well-recorded "classical" music, your P/A is 20dB AT BEST.   d) Not knowing what volume you prefer, but assume that you are averaging 1 watt into reasonably efficient speakers (those Fishers are that, at least). So, you will need no more than 100 watts of output for the very few peaks.   I doubt you have the XP10, or you would not have any issues with replacing the tweeter as that is a 2" soft dome, any decent one will do. But, as these go back to the days of Avery Fisher (1965 or so), you will be having surround-rot issues and more, which you are not reporting. So, I suspect you have one of their latter-day speakers that traded on the Fisher name, but without the quality.   Peter Wieck Melrose Park, PA

ohger1s@gmail.com: May 04 07:44AM -0700 > I never owned any Fisher tube gear, but I heard it was built well. > That's all I know about that, except it sells for big $$$ now.   I have a small collection of vintage tube hifi, mostly Scott and Fisher and one Mac and one Marantz. IMO the Fishers are the equal of any equipment made by any metric. I've been using a Fisher X1000 integrated as my main amplifier for decades (I have two of them actually), even when they were sniffed at by "audiophiles". I just love the combination of power and finesse of the 1000.   For a time, vintage Fisher tube equipment was pretty reasonably priced and undervalued (in context). My *opinion* on this is that Fisher was not only a beautifully designed and built product, but Avery Fisher was a good businessman as well. Fisher built a *lot* of stuff at reasonable prices (think Henry Ford meets Augie and Fred Duesenberg)   Since a lot of "value" is based on rarity, it's my opinion that Fishers were cheaper years ago then the average Marantz or McIntosh simply because there are so many more of them, but it seems collectors finally caught on to Fisher judging by what they're selling for nowadays.

mjb@signal11.invalid (Mike): May 04 01:36PM +0100 In article <e35a11da-efec-41aa-8dd1-21435405e0ed@googlegroups.com>,   >** This the one? >http://au.rs-online.com/web/p/precision-cleaners-degreasers/0180831/ >That is a strong grease solvent, meant for mechanical stuff.   Not that one. It was a *lot* of years back, and his since been used and chucked. A round can with screw-on lid, and internally a "reversible" aluminium delivery tube, which you rotated 180' and poked out through a hole in the lid to use it.   Khaki green print on white. No idea what the RS part code was, but it was "own branded".   But it was definitely a switch cleaner ... it never damaged a switch or pot, but it didn't agree with that thermoplastic case :(   -- --------------------------------------+------------------------------------ Mike Brown: mjb[-at-]signal11.org.uk | http://www.signal11.org.uk

oldschool@tubes.com: May 04 05:01AM -0400 000000On Thu, 4 May 2017 10:32:45 +1000, Trevor Wilson >device is, any assistance can only be of a generic nature. LED failures >are common, but it could be a connector. Who knows? Without more >information, it is impossible to say.   It's an Altec Lansing 1692A preamp mixer.   I was able to locate a poor schematic for it. Poor in the sense that the manual is a zip file containging about 12 JPG files that are all positioned sideways (I had to use a graphic editor to fix that), and it's very difficult to fit the pieces together. Plus there are sections missing.   After getting these schematics semi useful, I tore into the device. I playing music thru it while measuring voltages from the power board, which is putting out +15 and -15 volts (as it should).   The LEDs were working on one channel but not the other. Then all of a sudden one channel became disrtorted, then quit playing music. I removed the main board (which meant tearing apart the whole thing.   Using my old Paco audio tracer, I was able to determine that the audio signal works up to the 5532A op amp chip. (U9) It gets thru the first #1 section of that chip, and vanishes when it enters the second #2 section. That #2 section is also the driver for the LED display.   (However, with the board pulled, the LED display is not plugged in, because the readout LEDs are atached to the front panel, which cant be attached while signal tracing.   I decided to get the audio working on that channel first, before going back to the LED problem. That's when I touched that (U9) 5532A chip, and nearly burned my hand.   (The identical chip and circuitry on the working channel is barely warm).   So, I am pretty sure at this point that this 5532A chip is bad.   I will perform a check with my VOM to make sure there are no shorts, but aside from a few caps for the tone control section, there is not much to short out. (I looked for any bad solder joints and/or darkened resistors, everything looks fine).   I have a feeling that once I get the audio working properly, the LED meter may work. If not, there must be a bad LED strip. Which reminds me, can these strips be purchased?   These LED strips have 5 holes where pins plug into the, THey are labelled as:   1. -15V 2. +15V 3. Unregulated Power supply (+20V) 4. Connects directly to the preamp output 5. Common   I guess before I can do much more, I have to find a place to order a 5532A chip (or several of them so I have spares).   [I should note that I dont normally work on anything with IC chips. I repair tube equipment and sometimes some real early transistor stuff. But this is my own preamp, and if I dont fix it, no one will. Plus, this is a fairly simple circuit..... if only I had a better schematic].   I have to mention that my over 50 year old tube type Paco audio tracer has been the most valuable means to test this unit, but with one problem. The probe tip is too thick to get it on those tiny IC pins without shorting across two pins. And with my poor eyesite and shaky hands, it was near impossible. I finally used an alligator clip lead, with a piece of a paperclip for a probe tip, wrapped that paperclip wire in electrical tape, and clipped the other end to my probe.   WHAT THE HECK DO YOU GUYS USE FOR PROBES ON THOSE TINY PINS? DO THEY SELL SPECIAL PROBES OR PROBE TIPS FOR THIS PURPOSE?   The good thing is that all the ICs in this device are plug in socket types. Thank God for that!!!

tabbypurr@gmail.com: May 04 04:37AM -0700 > in electrical tape, and clipped the other end to my probe.   > WHAT THE HECK DO YOU GUYS USE FOR PROBES ON THOSE TINY PINS? DO THEY > SELL SPECIAL PROBES OR PROBE TIPS FOR THIS PURPOSE?   a pin sticks to the metal better. You could coat most of it if sight & steadiness are a problem.   > The good thing is that all the ICs in this device are plug in socket > types. Thank God for that!!!   I've had a lot of DIL socket failures.     NT

"Ron D." <ron.dozier@gmail.com>: May 03 09:19PM -0700 >Offhand, I would say you're correct, that Samsung doesn't make it easy to use a rotator or multiple antennas.   Oops, for your Samsung.   >Is the virtual channel number correct? Does it even have a virtual channel number?   Virtual is fine. In the details (MENU) In the DTV signal strength have:   freq: off air 57.00 MHz Power level and s/n with weak Normal type things. ss in dbm and s/n in db   In Manual scan, I'm asked to enter the "Channel Number" which is the physical one.   DST: It had already changed this year at 10 PM, not 2 AM.   EPG: My Bad, the remote labels it as such. It would be what's gonna happen on the current channel. That's totally part of the ATSC signal. It messes up a few hours before midnight. It's like 11:37 pm and it has programs that start at 12:30. After midnight it gets lots more. Another $50 government box works.   It's not the Master EPG programming schedule for all channels.   cable card- Yep.   RF Modulator? Sort of. One of these: http://english.dsdvb.com/Upload/files/Encoder%20Modulator/NDS3542A/3EEECN_20150304024149.pdf   4 channels of 4K HD video on 4 RF channels and 4 IP TV channels. Right now my wired Ethernet is too slow and wireless is even slower. I have not tried to see the RF output but I did measure a decent BER and signal strength on a test instrument w/o video)   Streaming: two-foldRF Modulator?   Be able to watch ATSC TV on the laptop (Slingbox like   AM/FM or anything L/R to HDMI ATSC Audio only in AC3 or Dolby Digital.   The smart TV does have a web browser, but you can't tell the TV to just do audio. You end up with a web browser screen with audio. For video the Samsung won't do Flash. ATSC TV's with converter boxes are everywhere in the house. My elderly Mom likes AM radio and can't yet operate the TV that detailed. She can't at this point watch youtube on the TV to watch the Sunday Mass.   Like I said, the TV is really dumb. A wireless USB keyboard won't work on youtube. Well,the arrows work, but the characters don't. They blame the app maker - i.e. Google for this. Nearly useless or DUMB!

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