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oldschool@tubes.com: May 18 01:15PM -0400 >using them tend to use moving coil cartridges.   >But the default is moving magnet.   > Michael   Good article on that website listed. I have two turntables. The cheap one has a non-removable (as far as I know) cartridge. I dont have a cartridge number, but its an AIWA turntable, and takes an AN-11 stylus. The good turntable has an Audio Technica AT5011E. I also have a spare cartridge from way back, (new in the box), Electro Voice V100.   I'm pretty sure the Audio Technica and the Electro Voice are both MM. Probably the AIWA one too, unless thats a crystal or ceramic.   I imagine there is a place to look them up, but I have not yet tried to find a website that lists them.   As far as using an ohm meter. I do understand the old analog ones are probably not a good idea. I do have a modern digital one (not one of those cheap HF ones). But what about using a VTVM. I may be wrong, but it's my understanding that VTVMs are safe to use on darn near anything. I have two of them, a Heathkit and an Eico.   (Presently the Heathkit one tends to act a bit flakey, probably needs new caps, but the Eico works fine).   But it's probably easier to just look them up by model.   Not to mention..... Both the AT and the EV have FOUR wires coming from them, but when they exit the turntable, they only have TWO (as in RCA plugs). What are the other two wires for?????

"pfjw@aol.com" <pfjw@aol.com>: May 18 12:02PM -0700 > those cheap HF ones). But what about using a VTVM. I may be wrong, but > it's my understanding that VTVMs are safe to use on darn near anything. > I have two of them, a Heathkit and an Eico.   Whoooo Boy! I can think of no reason whatsoever that one should ever use a VTVM in these modern times. Sure, loading a Zenith TransOceanic while performing an alignment via a VTVM makes some of the things go 'by the book', but using a regular high-quality VOM is just fine. Better in many cases. Nor would I ever advocate using a mains-connected VTVM on much audio stuff in any case. Nor do I appreciate them as ancient tools. I do not have enough real-estate on my bench to entertain tools that are not useful. > (Presently the Heathkit one tends to act a bit flakey, probably needs > new caps, but the Eico works fine).   > But it's probably easier to just look them up by model.   Wheeee.....   A typical stereo phono cartridge of any ilk has four (4) wires coming out of it. Some (very) cheap devices have only three, sharing the ground between the channels, but I have not seen one of those for over 30 years. > Not to mention..... Both the AT and the EV have FOUR wires coming from > them, but when they exit the turntable, they only have TWO (as in RCA > plugs). What are the other two wires for?????   So, we have:   SR/RG (signal right/right ground) SL/LG (signal left/Left ground)   Which goes to Right RCA Jack as follows:   SR to center post. RG to shell (shield).   And the left RCA Jack as follows:   SL to the center post. LG to the shell (shield).   Magically, four wires go to two wires.   There should be a general ground wire in there somewhere - which *SHOULD NOT* go to the pre-amp/amp chassis ground but to either of the shells on either of the jacks.   Peter Wieck Melrose Park, PA   One cannot make this stuff up!   On some great and glorious day the plain folks of the land will reach their heart's desire at last, and the White House will be adorned by a downright moron.   H.L. Mencken

ohger1s@gmail.com: May 18 12:38PM -0700 > On some great and glorious day the plain folks of the land will reach their heart's desire at last, and the White House will be adorned by a downright moron.   > H.L. Mencken   A true prophet.. Two in a row; a *long* 16 years (and one a socialist). Hopefully the next 8 years will be better.

Foxs Mercantile <jdangus@att.net>: May 18 02:52PM -0500 > Hopefully the next 8 years will be better.   It's just like watching The Lord of the Flies now.       -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

"pfjw@aol.com" <pfjw@aol.com>: May 18 01:18PM -0700 > A true prophet.. Two in a row; a *long* 16 years (and one a socialist). Hopefully the next 8 years will be better.   We have Tweedledumber as the incumbent, and Tweedledum standing in the wings. "Better" is a very relative thing. The incumbent is easily recognized for what he is - much like a hornet's nest hanging in the open. Or a baboon in a zoo flinging feces. The understudy is more akin to a common Krait. Far more subtle - and probably more dangerous if actually allowed power.   The US constitution is an interesting document. First, it is based on English Law vs. Napoleonic Law - do you understand the difference?   (Everything which is not forbidden is allowed" is a constitutional principle of English law—an essential freedom of the ordinary citizen or subject.)   Next, it contains the 9th & 10th Amendments (AKA - Bill of Rights) which supports the principle expressed above.   Then, and least understood: It does not speak to:   Marriage Flag Burning Homosexuality Christianity Islam Judaism Buddhism Shintoism Nor any other religion or belief system. Nor any of the other red-meat chimera so near and dear to neocons.   Nor, anywhere or in any where does it attempt to legislate morality. That is neither its purpose, nor should it be the results in its application.   Sorry for the ramble into politics - but this country has never been so threatened from within as now.   Let's call on one of the Founding Fathers - one who "got it right":   Freedom of speech is a principal pillar of a free government; when this support is taken away, the constitution of a free society is dissolved, and tyranny is erected on its ruins. Republics and limited monarchies derive their strength and vigor from a popular examination into the action of the magistrates.   Those who would give up essential liberty to purchase a little temporary safety deserve neither liberty nor safety.   Sell not virtue to purchase wealth, nor Liberty to purchase power.   Benjamin Franklin   Peter Wieck Melrose Park, PA

Ralph Mowery <rmowery28146@earthlink.net>: May 18 04:58PM -0400 In article <d5krhctif1agoutg0c47nhomo071l5vv01@4ax.com>, oldschool@tubes.com says... > I have two of them, a Heathkit and an Eico.   > (Presently the Heathkit one tends to act a bit flakey, probably needs > new caps, but the Eico works fine).   I have a Heathkit VTVM I put together over 40 years ago. I had it out a while back just to see if it still worked. It was slightly flakey and I gave it a shot of the Deoxit on the switches and that made it work like it did when I built it.   I don't know what kind of current it puts out in the ohms position. I doubt I will ever use it for anything but maybe where I need a zero center scale meter.

tabbypurr@gmail.com: May 18 02:17PM -0700 > Probably the AIWA one too, unless thats a crystal or ceramic.   > I imagine there is a place to look them up, but I have not yet tried to > find a website that lists them.   It's easy to tell magnetic from ceramic. Magnetic styli are in a squarish plastic piece that slides out - or rarely in the case of one of the AT unclips downward. Ceramic styli are unencased, and clip in. Old ones have a flipover sidearm to select from 2 needles, typically LP & 78.   The other way to tell them is to wobble the arm slightly when playing. Magnetics let the arm/needle wobble, ceramics don't.     > those cheap HF ones). But what about using a VTVM. I may be wrong, but > it's my understanding that VTVMs are safe to use on darn near anything. > I have two of them, a Heathkit and an Eico.   totally pointless.     > Not to mention..... Both the AT and the EV have FOUR wires coming from > them, but when they exit the turntable, they only have TWO (as in RCA > plugs). What are the other two wires for?????   Each RCA plus has 2 conductors, outer and inner.     NT

dplatt@coop.radagast.org (Dave Platt): May 18 02:25PM -0700 In article <ge0rhc1u4ivka1711na2ap84mjn8ratkbd@4ax.com>, <oldschool@tubes.com> wrote:   Yes, you got a lucky find!   I've bought a very nice receiver (a Proton) where the seller said it didn't work at all, and the reason was that he hadn't read the manual and seen that the receiver needs a jumper between "preamp out" and "amp in" if you aren't using an external signal processor. The original jumpers had been lost at some point and the owner didn't do his research...   >100 ohm   >Ok, I understand what they are saying, but how do I know if my cartridge >is MM or MC, and what the resistance rating is?   Ummm... search the Internet for its part number?   Or, measure its DC resistance with an ohmmeter. If it reads a few ohms, it's certainly a moving-coil amplifier. If it reads hundreds, it's probably a moving-magnet (there are some higher-impedance moving coil cartridges but they're less common).   The numbers you see above are not those of the cartridges... they're the parallel resistance of the phono stage itself, in that setting. The frequency response of any phono cartridge will depend to some extent on the load resistance. The cartridge maker may specify the recommended load.   >This appears to be a real useful thing, but I never even knew there were >different kinds of cartridges. In the past, I just installed a cartridge >and plugged it into "Phono".   Cartridges that you can do that with, are almost all moving-magnet (or moving-iron) cartridges. The MM setting, and 47k ohms input impedance, would very probably be the one to choose - that's the industry-standard resistance.   MC cartridges typically have a significantly lower output voltage... plugging them into an MM input will result in very low audio levels. One needs a bunch of additional voltage gain (provided by the preamp in MC mode, by an external "head amp", or by a signal transformer) to use a low-output MC cartridge.

rickman <gnuarm@gmail.com>: May 18 08:18PM -0400 >> it's my understanding that VTVMs are safe to use on darn near anything. >> I have two of them, a Heathkit and an Eico.   > Whoooo Boy! I can think of no reason whatsoever that one should ever use a VTVM in these modern times. Sure, loading a Zenith TransOceanic while performing an alignment via a VTVM makes some of the things go 'by the book', but using a regular high-quality VOM is just fine. Better in many cases. Nor would I ever advocate using a mains-connected VTVM on much audio stuff in any case. Nor do I appreciate them as ancient tools. I do not have enough real-estate on my bench to entertain tools that are not useful.   You are addressing someone who *just* discovered nanofarads. Consider his state of mind.   --   Rick C

Foxs Mercantile <jdangus@att.net>: May 18 08:03PM -0500 On 5/18/2017 7:18 PM, rickman wrote: > You are addressing someone who *just* discovered nanofarads. > Consider his state of mind.   That and RCA connectors actually have TWO connections.   -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com   --- This email has been checked for viruses by AVG. http://www.avg.com

oldschool@tubes.com: May 18 11:15PM -0400 On Thu, 18 May 2017 14:25:42 -0700, dplatt@coop.radagast.org (Dave Platt) wrote:   >"amp in" if you aren't using an external signal processor. The >original jumpers had been lost at some point and the owner didn't do >his research...   Sounds like you got a good deal too. I am very familiar with those jumpers. My Altec Lansing commercial power amp has those.   The guy that gave me this preamp did a similar thing. He thought that the RCA jacks marked "Output" were for speakers. That threw me off too, because he had said that, but in a matter of minutes I realized this is not a power amp. Looking it up online confirmed that.   About the only things that I recall using RCA plugs on speakers were some of those really old portable record players from the 50s and 60s. The speakers would unplug using a RCA jack/plug and the speakers lifted off the record player, using special hinges with pins that stuck out, so the speakers could be moved.

oldschool@tubes.com: May 18 11:36PM -0400 On Thu, 18 May 2017 16:58:43 -0400, Ralph Mowery   >I don't know what kind of current it puts out in the ohms position. I >doubt I will ever use it for anything but maybe where I need a zero >center scale meter.   That's something I should do with my Heathkit VTVM, use the Deoxit. Maybe that is all it needs.... But I do plan to recap it anyhow. At least the power supply lytics....   I use almost all old tube based test gear, but I normally only work on tube stuff, so I use what matches the equipment.   Lately, I have been working on a lot of solid state stuff. I'd rather work on tubes, but this soild state stuff is my own stuff, so I work on it. I generally use all modern test gear on solid state equipment, except for my old Paco tube signal tracer. That thing works on everything and is probably my most used piece of test gear.   But I like that old tube test gear, for working on tube stuff. My Sencore scope is solid state, but it's still quite old. I recently got all five of the old Eico probes, plus the high voltage probe they sold. So I am now equipped with probes for almost every need. Eico made the best probes ever, and I really had a tough time getting all of them. I'll probably never need the high voltage one, since I dont work on old CRT tvs, but it came with the other probes.   All I need now, is an old 50s era panel truck so I can paint "Radio Repair" on the sides!!!

oldschool@tubes.com: May 18 11:38PM -0400 On Thu, 18 May 2017 12:02:09 -0700 (PDT), "pfjw@aol.com" <pfjw@aol.com> wrote:     >A typical stereo phono cartridge of any ilk has four (4) wires coming out > of it. Some (very) cheap devices have only three, sharing the ground >between the channels, but I have not seen one of those for over 30 years.   Oops, I was having a brain fart. Yep, these are STEREO cartridges. They need FOUR wires (or at least 3 if they share the ground).

freeunixbsd@gmail.com: May 18 08:45PM -0700 hello i'm repairing a borad ,the board'silkmask is "4s015-119 386sx4".When i open the board's power,the two leds display BB,then change to b1,final ,the leds display "ee,h0,21".I search the internet but i get never informtion. Someone can give me the board's manu or download's url. Thx .

John Robertson <spam@flippers.com>: May 18 04:33PM -0700 On 2017/05/17 8:43 AM, Ralph Mowery wrote:   > Try searching for   > 862D+ 2in1 SMD Solder Soldering Iron Hot Air Rework Station   > There are many of them for just under $ 50.   Clear your cache. I get a No Listing for 122275067539.   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

Chris Jones <lugnut808@spam.yahoo.com>: May 19 09:56AM +1000 On 17/05/2017 23:02, bitrex wrote: > plated-through holes for replacement; it's resisted all my attempts to > pry it out using an iron/solder sucker or solder wick. I don't own a hot > air station unfortunately - any tips here?   If you have a hardware store type hot air gun with closed-loop temperature control then you may be able to use that. I recently had to use one set to 340 deg C to get a connector off, and that was one pin at a time. I needed the hot air gun again in one hand, to get the solder to melting point to clean out the holes with one of those desoldering irons in the other hand (with the vacuum pump). Even filling up the holes with leaded solder only made it slightly easier, but I could still not get some holes to melt right through with any soldering iron (including a Metcal with a very large, very hot tip), even with the board on a hotplate.

rickman <gnuarm@gmail.com>: May 18 08:10PM -0400 On 5/18/2017 7:33 PM, John Robertson wrote:   >> 862D+ 2in1 SMD Solder Soldering Iron Hot Air Rework Station   >> There are many of them for just under $ 50.   > Clear your cache. I get a No Listing for 122275067539.   I found it by doing a Bing search on the number directly from your post. (T-bird lets you do that)   --   Rick C

stratus46@yahoo.com: May 18 08:43PM -0700 > https://www.channellock.com/data/default/images/catalog/original/E338-842_1-842.png   > Peter Wieck > Melrose Park, PA   Rather than grind, I clip all the pins and extract one at a time. It depends if you're trying to salvage the part or just want minimum damage to the board.   When removing caps from computer mother boards I sometimes have to use a hot air tool in one hand and a Metcal iron in the other for the ground pins with no thermal relief on the internal pads. My hot air tool is one of those 862D units. I use only the air part which is also an excellent heat shrink tool.   G²

mikeberlak@gmail.com: May 18 05:21PM -0700 On Wednesday, March 15, 2017 at 5:53:01 PM UTC-4, David Farber wrote:   > --   > David Farber > Los Osos, CA     Hello David -- I just picked up a used RX707 that is doing the same exact thing...after heating up the right channel is distorting badly, but only when SEA is switched in. From what I can take from your discussion above, you solved the problem by adding 100k resistors from two of the pins of IC503 to ground? Which two pins get the resistors? Has that fix lasted long term? I love the fact that you can basically save a different EQ for each of your sources, something that today's products don't allow. Thanks for the info if you can provide it. Mike

bitrex <bitrex@de.lete.earthlink.net>: May 18 12:51AM -0400 On 05/17/2017 08:02 PM, Trevor Wilson wrote:     > **No, not the worst. It's the one that sticks in my mind, because it was > in the early days of my own business and, because I did not capitulate > to his threats, I did not lose any money.   You remember some dopey customer from when he was probably still playing the Saturday Night Fever soundtrack on that turntable and I was still being bottle-fed, and it wasn't even the worst?!

N_Cook <diverse@tcp.co.uk>: May 18 08:54AM +0100 On 16/05/2017 23:43, Trevor Wilson wrote: > business with him. Ever.   > FWIW: I have retained repairs for as long as 2 years, waiting for > customers to collect their jobs.   A large Roland Cube that bounced back about 6 times. Always the same reported problem of severe distortion on the lowest notes. The most difficult of repair jobs, finding a non-existent fault. Owner used this amp for his acoustic bass, as very light but could accomadate the double-bass notes. A serious case of RTFM. He was not interested in chorus,flange, amp types , just a basic amplifier , so except for volume and gain and tone he turned all the controls fully anticlockwise. That position on the mode? switch was octave bass.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 18 07:37PM +1000 On 18/05/2017 6:59 PM, Phil Allison wrote: > unit un-plugged he exploded at me saying he knew what he was doing > and turned off the power with the front panel switch.   > Oh dear........   **Those old SATO fuse holders were death traps. But yeah, I get your point. People in the music industry can be, uh, unpredictable.     -- Trevor Wilson www.rageaudio.com.au

jurb6006@gmail.com: May 18 12:57PM -0700 > "I knew I wouldn't need it for a while, so I thought I'd store it with you for two years".   Reminds me of a joke.   Guy in NYC is going on vacation and steps into the bank for a loan of like $20,000. Uses his Mazerati for collateral. Drops of the car and picks up the money. A couple months later he comes and pays the loan back with interest and they ask him "We checked your credit and found out you are a millionaire, whyu would you want to borrow a measely $20,000 from us ?   He said "Where else could I park my par that cheap ?   One of my halfway nice receivers came from a shop, a Marantz 4230. I was looking for a job but they weren't paying to my liking so I never worked there, but I did notice the receiver and inquired if it was for sale. They said it was "Gypsy bait". He said they knew exactly where it came from and was FUBAR bad in the amp. But every once in a while someone would come in and try to claim it.   Well amps were my specialty and this thing had three channels blown. It origianlly used those TO-220 modificsations when the heat sinks were drilled for TO-66. I found some suitable TO-66 transistors, fixed the three channels and refittted the one with the TO-66 transistors. In bridged mode the power was almost respectable.   I sold it off to a buddy who used it as an integrated preamp. Later I ran across a 4270, in ridged mode it clipped at 154 a channel in stereo, and I used the pre-outs to drive a rear amp. Now that was system. There were more cable behind it than you could shake a stick at. It had both beta and VHS and the ability to dub either way, on top of cassette and all that other stuff, plust two equalizers. In the middle (corner actually) was a five foot Advent, the kind with the silver screen and mine was one of the few that worked right. The convergence was damnear perfect and someone had obviously changed the tubes. All this stuff came from shops except the beta.   But I like that term "gypsy bait". Especially when you have been in the same location for over 20 years. Especially when you know where it came from and why you have it, three channels blown, imagine the repair bill on that. Once I gathered all the parts I stayed up all night to fix it so that gave me about six hours into it, after the diagnosis and parts procurement.   But we've had people who wanted to come and look around the shop for "their" TV.   Scam artists are plentiful in this country, or at least this area. In the N Cook thread someone said "I am glad I am not where you're at". Well I should have moved out a long time ago.

rickman <gnuarm@gmail.com>: May 18 08:16PM -0400 > Scam artists are plentiful in this country, or at least this area. In the N Cook thread someone said "I am glad I am not where you're at". Well I should have moved out a long time ago.   It was me. I wasn't talking about your location, but your state of mind. If something messes with your head that much, it's time to move on in whatever way is needed.   --   Rick C

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 18 07:39PM +1000 > alot of Marantz prints. I was actually surprised to see it, and it > was the only one. I remember it was a lower end model but it still > had the Marantz look.   **I could be wrong, but I doubt it. Luxman, absolutely. Quite a few of theirs employed such a system. If you figure out which Marantz, let me know. I have pretty much every service manual for every model.       -- Trevor Wilson www.rageaudio.com.au

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