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bitrex <bitrex@de.lete.earthlink.net>: May 17 09:02AM -0400 I have a Behringer EQ that has a bad front panel switch. It looks to be a standard 3 pin SPDT type, surrounded by a metal bracket that holds it fast to the PCB.   I've been having a lot of difficulty removing it from this PCB with 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?

tabbypurr@gmail.com: May 17 06:25AM -0700 On Wednesday, 17 May 2017 14:02:59 UTC+1, 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?   With PTH you need to get lots of heat into the board - removing solder achieves the opposite. Put the sucker & braid away and solder it, then you can heat one pin at a time and bend the board ever so slightly, and slowly walk it out. Yes, it's slow. No, you mustn't overheat anything.     NT

ohger1s@gmail.com: May 17 06:32AM -0700 > > air station unfortunately - any tips here?   > With PTH you need to get lots of heat into the board - removing solder achieves the opposite. Put the sucker & braid away and solder it, then you can heat one pin at a time and bend the board ever so slightly, and slowly walk it out. Yes, it's slow. No, you mustn't overheat anything.   > NT   Not a good plan IMO - if it's just a top and bottom conductor board, maybe. But if it's a multi layer I wouldn't try it. That kind of manipulation can cause a detachment of a middle layer conductor that would be tough to solve without a schematic or an identical board to trace out.   But you're correct about heat. When working on multi layer boards that require multiple through the hole pin extraction, I preheat the board to 125C and let it soak 15 minutes. Add some liquid flux and solder removal techniques are usually effective.

bitrex <bitrex@de.lete.earthlink.net>: May 17 10:05AM -0400 >> NT   > Not a good plan IMO - if it's just a top and bottom conductor board, maybe. But if it's a multi layer I wouldn't try it. That kind of manipulation can cause a detachment of a middle layer conductor that would be tough to solve without a schematic or an identical board to trace out.   > But you're correct about heat. When working on multi layer boards that require multiple through the hole pin extraction, I preheat the board to 125C and let it soak 15 minutes. Add some liquid flux and solder removal techniques are usually effective.   Thanks for the advice guys. I have a schematic available fortunately; I'll have to take a closer look at the board but since it's Behringer my guess is that a double-sided board at most heh heh ;-)

rickman <gnuarm@gmail.com>: May 17 10:31AM -0400 On 5/17/2017 10:05 AM, bitrex wrote:   > Thanks for the advice guys. I have a schematic available fortunately; > I'll have to take a closer look at the board but since it's Behringer my > guess is that a double-sided board at most heh heh ;-)   Yeah, double sided is not so bad, but it can be hard to deal with the triple sided ones. ;)   --   Rick C

Ralph Mowery <rmowery28146@earthlink.net>: May 17 10:37AM -0400 In article <4SXSA.149693$Qa2.68261@fx10.iad>, bitrex@de.lete.earthlink.net says... > 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?   With the hot air rework stations from China at only $ 45 you may want to look into getting one. While they probably will not hold up under heavy usage, I have one and it works fine for hobby use. YOu get the hot air gun and a soldering iron that heats up very fast.   Here is one from ebay.. 122275067539

rickman <gnuarm@gmail.com>: May 16 09:05PM -0400 > A or B but not C ..... and no, I haven't connected led to load to grnd in series. I lit ank added LED for connection to power not grnd. All the successful connections here go directly to grnd thru the relay. Not thru load. I had thought. without theory, that this was connected to the total Ford system activating power to grnd. try separating application and demo in the same circuit ....   > an excellent question. I needed 20 steps up from the keyboard when your question became obvious.   > I give out Bcae's address to 'mechanics' like myself n they have results.   Which switch do you have? Is the LED INSIDE the switch?   --   Rick C

avagadro7@gmail.com: May 17 06:44AM -0700 On Tuesday, May 16, 2017 at 9:05:30 PM UTC-4, rickman wrote:   > Which switch do you have? Is the LED INSIDE the switch?   > --   > Rick C   the rockers I use are 3 pins as in Bcae's link above.   here is the gamut   https://www.amazon.com/b/ref=sr_aj?node=3398751&ajr=0   the Chinese have road tested fat tired glass packed Ford pickups ...   All E has new stock .....stating with 'built in resistors for 12Vdc .....   http://www.allelectronics.com/category/720/switches-rocker/1.html   why resistors ?

rickman <gnuarm@gmail.com>: May 17 09:52AM -0400 > All E has new stock .....stating with 'built in resistors for 12Vdc .....   > http://www.allelectronics.com/category/720/switches-rocker/1.html   > why resistors ?   I give up. The pages you point to show dozens of switches. I'm not going to try to read your mind. If you can't tell me what switch you are using, I'm not going to try to guess how to wire it.   --   Rick C

Phil Allison <pallison49@gmail.com>: May 16 06:50PM -0700 > AR made the 4X for very nearly Fifteen (15) years. Well over 300,000 > were made.   ** Few were sole here in Australia and some were made here too.     > What you are showing is a *VERY* early version from the late 60s. > AR started with the Chicago-made box caps early on. For a reason > so obvious, even you should be able to figure it out?   ** The same type of caps were in my pair of Us made AR2Axs, totally stuffed.     > You keep reasoning from the specific to the general.     ** I did not do anything of the kind.   As per usual, you have deleted my entire post and forgotten what it ACTUALLY says. Usenet etiquette *requires* you to QUOTE the parts of a post you are responding to.   This avoids such errors, ambiguity and allows further responses to REFER to the exact words.   You claimed that AR did not do thing the cheapest possible way.   They did and more often than not.   I supplied a pic of ONE example of what I meant.   FYI:   Two friends of mine owned pairs of AR11s, built here under license using kits supplied from the USA, in the late 70s.   The x-overs used non-polar electros feeding the dome mids and tweeters.   Replacing these with 200V, polyester film caps made a VERY audible improvement.   You are so full of shit.     .... Phil

Phil Allison <pallison49@gmail.com>: May 16 08:34PM -0700 Phil Allison wrote:   -------------------     > The x-overs used non-polar electros feeding the dome mids and tweeters.   > Replacing these with 200V, polyester film caps made a VERY > audible improvement.   ** Evidence from 1978 built AR11.   http://www.oaktreevintage.com/web_photos/Speaker_Parts/AR-11_Crossover_Network_web.jpg       .... Phil

gregz <zekor@comcast.net>: May 17 08:00AM > cap(s) for an electrolytic, some experimentation may be required as these > days, the tolerances for film caps are commonly less than 2%. As compared > to as much as +50% for electrolytics.   Sometimes you need really big values. I have measured many electrolytics that are very close to marked value, at least ones in good shape.     > This is a crossover from an AR4x speaker, contemporary to the A25, and > also well respected. But from a manufacturer that did not do things in > the cheapest possible way. Note the inductor, and non-electrolytic cap.   Some simple caps change crossover points with variable attenuator in series. So you get level and phase change at the same. Not great idea.

Phil Allison <pallison49@gmail.com>: May 17 01:19AM -0700 Phil Allison wrote:   ------------------     > ** AR normally built their speakers in the CHEAPEST way possible.   > That white cap in you pic is clearly non original ...   ** The pic IS of a **REBUILT** AR4X crossover.     http://www.classicspeakerpages.net/IP.Board/index.php?/profile/101828-jkent/content/&type=forums_topic_post&page=12   Wot a stinking fake.     ..... Phil

Phil Allison <pallison49@gmail.com>: May 17 01:25AM -0700 GS wrote:   ------------------------   The Peter Wieck liar posted: http://www.classicspeakerpages.net/IP.Board/uploads/monthly_2016_09/57cf896d9937f_AR4xxo.jpg.3825ebd29785aceb6ff415ce4b6b4d7b.jpg > > the cheapest possible way. Note the inductor, and non-electrolytic cap.   > Some simple caps change crossover points with variable attenuator in > series. So you get level and phase change at the same. Not great idea.   ** The pic quoted by "pf" is of a RE-BUILT AR4X crossover.   The Zen cap is not standard in any version nor is the L pad.   AR normally used a simple, WW pot, which is pretty darn slack.   IME, AR were seriously into cheapness.       .... Phil

Phil Allison <pallison49@gmail.com>: May 17 01:51AM -0700 GS wrote:   -------------   > Sometimes you need really big values. I have measured many electrolytics > that are very close to marked value, at least ones in good shape.   ** If the large value electro is wired in parallel with the woofer, it does little harm. Non linear distortion products do not transfer to the mid or treble drivers. FYI:   My last project involved completely stripping and re-engineering an old pair of AR2Axs - the cabs were in good nick and cost me $100.   I fitted Peerless, 10 inch woofers ( 830668 ) with a 12dB/oct filters that used non-polar electros and a 2mH air inductor.   The mids were 4inch Peerless ( PL11MH09-08 ) with 12dB/oct filters at 450 Hz and 3kHz, using only 250VAC rated film caps and air inductors. I installed a thick walled, cardboard tube from back to front to give this driver its own, 2 litre enclosure - stuffed with absorbent wadding.   The tweeters were 4ohm PAE 1 inch soft domes ( PAE 25TG18) with an 18dB/oct filter using 250AV caps and air inductor.   I spent considerable time doing tests with an AKG CK2 condenser mic using 1/3oct pink noise and 4 cycle tone bursts.   There are a couple of 5 watt WW resistors involved, no variable attenuators and the final touch was to install Speakon connectors.   On good programme, they leave any AR I have listened to for dead.     .... Phil

Phil Allison <pallison49@gmail.com>: May 16 06:36PM -0700 pf...@aol.com wrote:   ----------------------   > > Other than that, yeah, a small drill does fine and a dab of RTV will cover the hole nicely.   > > Either method take very little time.   > So, tell me, without removing the pot from the device, even with a good vacuum cleaner, would _YOU_ wish to use a drill and possibly let metal shavings into something?   ** In most cases, one drills into plastic.   In other cases the swarf is easily removed.     > And, if the pot is coming out anyway,   ** Of course it is not coming out.   Forcing fluid around the shaft and its bearing is to be avoided - since it removes the layer of grease that gives pots their silky feel. On trick I sometimes employ to save disassembly / reassembly time is to remove the knob and hex nut, then drip some WD-40 around the thread with the shaft pointing upwards. It soon find its way onto the track and presto.     .... Phil   .... Phil

Jeff Liebermann <jeffl@cruzio.com>: May 16 08:03PM -0700 On Tue, 16 May 2017 18:36:39 -0700 (PDT), Phil Allison   >Forcing fluid around the shaft and its bearing is >to be avoided - since it removes the layer of grease >that gives pots their silky feel.   Damping grease: <https://www.nyelubricants.com/damping-greases> I have some for lubricating microscope gears. Kinda expensive, but a small tube lasts a long time. No way to re-lube a pot without disassembly: <http://www.ebay.com/itm/Lubricant-Grease-Nyogel-50g-Tube-/401292936041> The problem with re-lubricating pots on a hi-fi or whatever with several pots on the front panel, I would probably need to re-lube all the pots to make them all feel the same.   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

whit3rd <whit3rd@gmail.com>: May 16 08:18PM -0700 On Monday, May 15, 2017 at 1:05:38 AM UTC-7, GS wrote:   > How long have I used it on stuff? I keep wondering, at least over 40 years. > I know in the 60s I had some electronic cleaner that really melted some > plastics good.   Probably that was Freon TMC (the 'MC' was methylene chloride); it was the right stuff for some gum removal, but not nice to paint or plastics.

gregz <zekor@comcast.net>: May 17 08:12AM >> plastics good.   > Probably that was Freon TMC (the 'MC' was methylene chloride); it was the right > stuff for some gum removal, but not nice to paint or plastics.   I seem to remember the name, like swish or wissh. Wisshed I hadn't used it.   Greg

Phil Allison <pallison49@gmail.com>: May 16 09:18PM -0700 Hi TW,     I have a Marantz SR2000 on the bench with both STK080G modules blown and signs of attempted repair. I know the PSUs and tuners are OK.   WES does not stock the 080G but has the uprated 083G which appears to be pin compatible.   Can it be a drop in replacement?   Any mods needed ?       .... Phil

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 17 02:56PM +1000 On 17/05/2017 2:18 PM, Phil Allison wrote:   > Can it be a drop in replacement?   > Any mods needed ?   **Puke. Worst. Marantz. Products. Ever. Cheap shit. Lemme check for any 080s I may have in stock.   I have one STK-080-II in stock. It will almost certainly be a drop-in replacement. Not sure about the 083G.   Looking at the .pdf on this page, suggests that it will be a drop-in replacement:   http://www.datasheetspdf.com/datasheet/STK083G.html   I don't think you'll have a problem. Piece of shit SR2000. All the SR range was crap, along with the tuners and integrated amps at the time. That was built at a time when Marantz was in deep shit. The Pianocorder™ almost sent them to the wall and the quality of their audio products went downhill real fast. Then Philips bailed them out and the quality returned. One product they released almost did make me puke - Imperial, by Marantz (no, not the speaker systems). A return to those 1960s, single unit stereo systems. Plastic moulding, made to look like wood. Spectacular example of bad taste. I measured one. 1.75 Watts/channel. Yikes!   I just checked the web. I can't find any reference to the atrocities anywhere.   Fuck I hate Sanken shit and I wish manufacturers would stop using their semis. Bastards delete items forever, making it impossible to service old products.     -- Trevor Wilson www.rageaudio.com.au

Phil Allison <pallison49@gmail.com>: May 16 10:22PM -0700 Trevor Wilson wrote:   -------------------     > replacement:   > http://www.datasheetspdf.com/datasheet/STK083G.html   > I don't think you'll have a problem.     ** Yep - I found that data sheet earlier today.     > Fuck I hate Sanken shit and I wish manufacturers would stop using their > semis. Bastards delete items forever, making it impossible to service > old products.   ** The STK series is made by Sanyo.   Sanken modules, with numbers like SI1050 disappeared decades ago.   Both typically suffered from lack of short circuit protection.       .... Phil

jurb6006@gmail.com: May 17 12:01AM -0700 >"Fuck I hate Sanken shit and I wish manufacturers would stop using their semis."   I had a Mitsubishi X-11 system the guy's olady was in love with. Had a bad SI series output chip. I ended up wiring in a pair of LM3886s which use almost no external components. Worked fine.   I would have considered just runing pre-outs from it so he could connect an external amp but they put the tone controls in the global feedback loop.   I agree that Marantz went to shit. I've actually seen a few with the tone controls in the global feedback loop. Marantz ? In my book that is no Marantz. Now a 2325, things of that vintage, now that's Marantz.

ohger1s@gmail.com: May 16 07:19PM -0700 On Tuesday, May 16, 2017 at 6:44:07 PM UTC-4, Trevor Wilson wrote:     > -- > Trevor Wilson > www.rageaudio.com.au     I've done the same. If I call a customer and they either answer or return my call promptly, and tell me they want the item but don't have the money, I'll hold it for them. I'm not a pawn shop.   I've been in business for over 40 years and I can come up with some stories, but I'm going to switch gears from scamming customers and relay one of my favorites:   Back in the early 1980s, I did a house call for a Zenith System 3 console (for you old timers, this had the old 9-160 power/sweep/HV module in it). This module usually had a blown LOT/Flyback, horizontal/line output transistor, and other associate stuff. You knew this when you saw how the fuse vaporized it's wire and deposited it on the glass. A quick resistance check from hot ground to the TO-3 metal case collector showed zero ohms.   Anyway, the guy was over my shoulder and under my armpit insisting the TV must only need a new fuse. I knew it was no use explaining that there was no sense in even trying it if it was blown because he was sure that's all it needed.   So I installed a 7 amp fuse to replace the 4 amp and told the customer to get down real close and tell me if the fuse opened when I went around the front of the TV and pushed the power button.   I heard a soft pop like a flash bulb going off and I could see the customer's silhouette against the wall for a split second. He stood up from behind the TV blinking his eyes while I asked him if the fuse blew. He gave me trouble when I went out to the truck to get a new module.

rickman <gnuarm@gmail.com>: May 16 09:07PM -0400 >> your states' laws to see how this situation plays out in your area. >> Know your rights, and your obligations.]   > We don't have a law like that here in UK. Customers are routinely taken advantage of.   There is no such law here in the US. That sort of thing is regulated at the state level and good luck getting anything done about a shop without having to rent a car until the matter is settled.   --   Rick C

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