pingu
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Post by pingu on Jun 12, 2013 23:59:08 GMT
Aha, found it here and onwards. Adding a late "Thanks" Marc a really nice bit of work. Well done Martin
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pingu
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Post by pingu on Jun 3, 2013 11:04:24 GMT
Both Marc, only matched on a DMM but easey get matchs within 10%... maybe I was just lucky tho. I also have a local RS so can collect if it helps Martin
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pingu
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Post by pingu on Jun 3, 2013 10:52:48 GMT
Sorry Marc, Dissregard the last post I see what you mean. Wasn't questioning your maths just trying to be helpful. BTW if you want the free postage option just shout, but maybe on your order it will qualify for free postage anyway Regards Martin
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pingu
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Post by pingu on Jun 3, 2013 10:46:56 GMT
Hi Marc, Have you looked at Mouser Electronics they do good discount for bulk buys of 100 or so transistors. Martin[/quote]
I've just done a quick search on Mouser and 100 of each of the BC transistor (700 in all) comes to about 56.00 Euro. I have an account with them and if it helps I can order them for you with no carriage charge and forward them to you. I bought a load of 2SA1930 and 2SC5171 for the JLH ripple eater and found them to be very close indeed just as they cane so should be no worries about thier matching, All The Best Martin
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pingu
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Post by pingu on Jun 3, 2013 10:16:39 GMT
For all transistors, this price is based on buying 100 per type and dividing this total cost amongst the total needed numbers. This allows for matching, but it leaves a lot of waste. I haven't decided yet how it could be managed in a more fair way and it could end up being cheaper if I find a way. Read more: rockgrotto.proboards.com/thread/8894/class-pcb-parts-group-buy?page=9#ixzz2V99u5oUUHi Marc, Have you looked at Mouser Electronics they do good discount for bulk buys of 100 or so transistors. Martin
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pingu
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Post by pingu on Jun 2, 2013 12:49:06 GMT
Hi Marc, Can you put me down for HA/Pre Boards x4 LS352 & LS313 x4 PS PCB x6 Parts x2 My neighbour may have droped out but I'll take a set of HA/pre, PSU boards and a LS352 & LS313 set for him and if he is out use them as a mule. Thanks Martin
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pingu
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Post by pingu on May 4, 2013 22:49:01 GMT
Hi, I second Alexs warning. After a bout of auto immune eurticaria I lost 50% of my hearing and untill it goes you really do not know how difficult it makes life. Yes I wear two aids but they are a help and nowhere near ideal and make using cans difficult On the up side my daughter has a reason to call me a "deaf old fart" now as I collect my pension Take care Regards Martim
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pingu
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Post by pingu on May 2, 2013 10:51:38 GMT
Hello, maybe it's a wrong thread to ask but has anybody had any problems registering/buying a Panda kit recently? I tried to make an account at mall.hifidiy.net but have never received a confirmation letter, hence, can't shop. Tried to contact them via both support emails and the page form but they've never responded, it's been almost 3 weeks since my first mail. Any clues what's going on with them? Hi invidiy, try "panda pcb" search in Ebay and you should come up with two sellers, both buy it now options, post free to most places Martin
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pingu
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Post by pingu on Apr 29, 2013 9:59:03 GMT
Hi Shaun, Well I thought I had double checked everything, and the cat who sits on the end of the bench when she visits DEFINITELY check all the bits out. Obviously we were both mistaken. Martin
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Post by pingu on Apr 28, 2013 22:40:18 GMT
Thanks Will, good to know all this... If I have some time, I'll try to do a prototype with local parts only to have a small taste... Rgd Hi asdiax, Nice to have you join us, they are all very helpful on here (and I need it too ). If you have real problems with parts I have a local Radio Spares so can pop into the trade counter and collect any bits and post them on to you if the parts are small. That way there is no minimum order, if that is any help. Shaun and all the others who were invaluable to getting this sorted, PSU's up and running and the JLH RE's seem OK with them. Small accident when I miss connected one and had a cap pop on me. A "stray" cat was visiting at the time she left very quickly tho and took nearly an hour to venture cautiously back. My thanks to everyone who helped me to get them working. Next step the Brice HA while I wait for the GB Once again Thanks to everyone who helped
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pingu
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Post by pingu on Apr 12, 2013 12:56:30 GMT
Martin Shaun's replies have covered this pretty well. Alex Thanks Everyone, (Alex, Shaun, Jon) I shall reconfigure the REs to use 2200Ufs and a CL for the SC HA and leave the ones on the Brice HA with the 4700Uf no CL as earlier suggested because it uses about 200/250ma @ +/-12v. I have read the site Jon pointed me to and "think"( ) I have an idea now. Thanks Jon. No doubt there will be more probs/questions when the SC Ha build starts.... so pls be gentle with me . All the Best Martin
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pingu
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Post by pingu on Apr 11, 2013 11:18:38 GMT
Hi Shaun, Flux what flux? Bakers fluid... tastes much better. All soldered up now. The JHL RE has not got the CL in it and the caps are 4700Uf 16v with the 4700Uf 10v in the normal/low ESR as suggested in the previous posts... hope that is OK Will a single PSU supply enough power for a stereo SC HA BTW? All coming together now Martin
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pingu
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Post by pingu on Apr 11, 2013 10:29:55 GMT
Hi Everyone, Just waiting for the postie to deliver the caps for the PSU Shaun sent me and then it will be complete. One question about Txs, if I get one of the cheapy 18v 80va txs that Shaun uses can I power two PUS's and two JHL RE's to run a stereo SC HA? I was just wondering as these Tx's are so over spec'd (but very economical...Sir as the sales assistant says lol) would they be Ok and I could save some space too, or would it be better to use two Tx's? Martin PS update Postie just delivered the caps soldering iron heating up PSU will powered up when Tx's are purchased. Martin
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pingu
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Post by pingu on Apr 2, 2013 23:28:58 GMT
Thanks to both Alex and Shaun, your comments taken on board and changes noted. When I get the caps for the PSU and power up I'll let you all know how it goes. When the smoke has cleared of course. Looking forward to the SC HA project mmmmmmm John. Amazing work I will never get to that level very well done All the best Martin.
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pingu
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Post by pingu on Apr 2, 2013 13:25:49 GMT
Don't do that ! It will put a s/c across the transformer windings. Ooops Thanks Alex I see now. Silly miss reading of the circuit board I have PM'd you Thanks again Martin
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pingu
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Post by pingu on Apr 2, 2013 11:31:02 GMT
Thanks Shaun, just read your comments and as I am a bit deaf (as well as dim...lol) often wondered about boutique bits but assumed it was my faulty hearing aids tee hee. Yes getting some middle of the road long life general purpose caps from local RS for around a quid rather than over £2.00 The project moves on. Martin
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pingu
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Post by pingu on Apr 2, 2013 11:23:47 GMT
Thanks Alex all clear now. I couldn't work out from the board how the anode/cathode of D2/D3 were conected if C1 was left out. The pix shows it clearly (my eyes are a bit dim at times). I have bridged the C1 position. I have all the resist/cap values now thanks Martin
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pingu
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Post by pingu on Apr 2, 2013 9:02:27 GMT
Thanks Alex, help much appreciated and that has saved me some pennies too. I will crack on and get the caps now. I am working without a schematic of Will's PSU (I think it is the one for the SC HA with the 337/317 regs on it) and have looked on here but can not seem to find one. I am sure I have missed it, would you know where one is? Thanks again martin
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pingu
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Post by pingu on Apr 1, 2013 16:43:30 GMT
Hi Alex, I have now copleted 90% of the PSU boards (Will's Dual Reg) that Shaun kindly sent me (thanks again Shuan) but I am about to order the caps for them and I was wondering should I use "audio grade", low ESR types or just whats "in stock" these are the caps C2 to C6. Also C1 the small 470Nf 100V cap, as I am using fast schotsky doides is it needed? The PSUs will be used before the ripple eaters in the SC AH projcet and when some PSUs from the GB arrive they will be used to power a +/- 12v Richard Brice HA from an old HFW project. I have used the SF 14 diodes as no 12's were around ATM and some thin film 0.6wat resists from RS (good pice). It seems you have the Knowledge so may I pls pick your brains? Martin
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pingu
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Post by pingu on Mar 30, 2013 23:10:58 GMT
Having had a look at this amp on u tube it certainly looks a tiny bit of kit and is well presented. HFW usually do good reviews on the stuff, I would be inclined to trust their view more than other mags, and 5 globes is good. However the long lag between order and shipping is a worry for a mass produced item (at least from my point of view), it could be your young lad is financing his orders from customers payments?? (just under the credit card grt limit too ) But as Mike says £99.00 it is certainly a good price Martin
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pingu
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Post by pingu on Mar 29, 2013 23:39:12 GMT
Martin In all seriousness it's just another well performing opamp based headphone amplifier. There is nothing too special about it's design. Frans de Gruitjer's design was far more comprehensive, and also had user controls such as gain adjustments, bandwidth adjustments and was better able to match different types of, and different impedance headphones due to internal user selectable switches.That guy's main claim to fame was being banned from HeadFi. That's nothing special either, as Mike managed to do the same long before him! Regards Alex LoL banned from Head Fi....... my daughter got banned from the local deaf club when she was learning sign language ...... for shouting. (got a bit carried away with her arguement , arts graduate too) Looked at his web site and I thought it was a bit "too good" especially the ordering times. Seems he can make a bit on the money in the bank for a few weeks and a "proper" supplier can send by return, just struck me as a bit of a chancer, and wondered who/where it was being put together. No offence to anyone intended just my impressions. I'll stay with the JLH H/A Thanks all for the info Martin
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pingu
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Post by pingu on Mar 29, 2013 21:10:38 GMT
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pingu
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Post by pingu on Mar 25, 2013 22:18:59 GMT
Hi Chris, I agree with Chong and Martin. My personal preference would be the UF diodes set up in normal bridge rectifier configuration. To my bodging mentality, I'd make sure that the diodes that run from AC in to + DC out and AC in to - DC out are the ones that take the through-hole positions, then tag on the other two diodes to the exposed legs of the first pair. When bodging like this I like to make sure there is a mechanical connection before the soldered one. Therefore I'd hook the legs of the second pair around those of the first so that they hold even before any solder is applied. probably just paranoid-android stuff though Thanks Martin, Chong and Chris. Using ultrafast diodes directly onto the board seems the easiest way of doing things I have a slack hand full of UF4007 ultrafst diodes leftover from my V2 - can I use these? the only problem is they are rated at 1amp do you think I would have any problems with these or should I use some different types? Thanks again for the advice. Chris Hi Chris, CJ is about right I think Seems that it is a 24v input so diode of at least double plus a bit more (not sure how to work that bit out I just add about 150% to the voltage and the same to the amps). So at least 60v better 75v or 100v. Amps I always double the amps so 6 amps sounds about right. These are a bit higher voltage but the amps are OK 8amp 600v so Ok for mains if you buy a few. http://docs-europe.electrocomponents...6b80f8c96e.pdf from RS and not too expensive. I think any ultra fast soft recovery diode around 100v 6a will be OK tho. So maybe Farnell, Mouser, or Rapid will have cheaper ones. May be I am not correct but over spec for diodes in rectifiers seems to be what people use. Martin
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pingu
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Post by pingu on Mar 23, 2013 0:37:49 GMT
Hi Chris If the PCB is actually marked 100 , and 470, then that should be their actual values. Kind Regards Alex Hi Alex I have heard from the supplier and the values are what you said - Thanks. Next bit of help needed, can you tell me from the colour code of a resistor what the wattage is. It is an 0R22 resistor - colour code - Black, Red, Red, Silver, Brown. I also need help with the bridge rectifier, the one I ordered is far too big with the pins offset as you can see from the pic below. The space between the holes is 13mm and I think the rectifier sits on top with no heat sink. Not sure where to start looking so any help appreciated. Chris Hi Chris, If you just use 4 ultra fast or Schottky diodes in the ususal 4 pointed mode on a bit of vero board or just use the circuit board and adapt the connections that will do the trick. I am told it is better to use diodes than the bridge rectifers anyway so try this; www.world-designs.co.uk/forum/showthread.php?t=4131&highlight=schottkies&page=5Post 48 by Richard Also if you read that thread I think you can get rid of those caps by using the ultra fast diodes. Martin
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pingu
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Post by pingu on Mar 17, 2013 22:40:03 GMT
Hi Florian, your request is noted. When I find the time to update the participants list, I'll add you. I'll also do a price estimate for all parts. Cheers, Marc Hi Marc would appreciate an estimate too ...... no rush at all just curious. When you have time will be fine and I am aware it will be only a very rough estimate so no worries. All the best Martin
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