Sub Sonic Posted February 22, 2016 Share Posted February 22, 2016 So.....you're pretty much replacing EVERYTHING? Wow Except, perhaps, the V-FETs. 3 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 23, 2016 Author Share Posted February 23, 2016 So.....you're pretty much replacing EVERYTHING? Wow It is a restoration! All the ageing parts will be replaced. Some upgrades (diodes) were a recommendation, I already have tried the modification on another B-2, this was the best noise reduction mod, when the B-2 was made the technology of this diodes was unavailable. Link to comment Share on other sites More sharing options...
analog brother Posted February 23, 2016 Share Posted February 23, 2016 (edited) big jobs maaaaaaa Edited February 23, 2016 by analog brother 1 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 23, 2016 Author Share Posted February 23, 2016 (edited) On the the power supply/protection board. Relay state is pretty bad. 2 new relays, Omron LY2-0 12V DC are in. The transistors 7 and 8 get really hot so were replaced with MJE15032 and MJE1503. All glue cleaned up, and the heatsinks glued back to the board. Also, all the C458 transistors were replaced with C1518 's and 2 double diodes with 2X1N4148 for reliability. Caps with Nichicon KZ, and FG (fine gold) 6 metal film AMCO 0.01 also installed. 4 electrolytic bipolars were replaced with Nichicon Muse ES, 2 new trim pots. the original one were 4.7k, new ones 5k. Measure the trimpots when off and then adjust the new ones before installing, that way will have a good starting point for the +85/-85 rail voltages of the power supply. Old caps, bulging and starting to leak Edited February 23, 2016 by vintagejapan Link to comment Share on other sites More sharing options...
vintagejapan Posted February 23, 2016 Author Share Posted February 23, 2016 Except, perhaps, the V-FETs. V-fets are the magic.. 1 Link to comment Share on other sites More sharing options...
Guest Posted February 23, 2016 Share Posted February 23, 2016 Except, perhaps, the V-FETs. Oh you know I have no idea what that means But I see lots of soldering....so....big job It is a restoration! All the ageing parts will be replaced. Some upgrades (diodes) were a recommendation, I already have tried the modification on another B-2, this was the best noise reduction mod, when the B-2 was made the technology of this diodes was unavailable. Would it be rude to ask how much all the bags of bits in post #2 cost? Just curious how much a job like this is worth. Link to comment Share on other sites More sharing options...
vintagejapan Posted February 23, 2016 Author Share Posted February 23, 2016 Oh you know I have no idea what that means But I see lots of soldering....so....big job Would it be rude to ask how much all the bags of bits in post #2 cost? Just curious how much a job like this is worth. Looking at around $250~300 right now for all the parts. Link to comment Share on other sites More sharing options...
vintagejapan Posted February 23, 2016 Author Share Posted February 23, 2016 (edited) Ok power board done. Here is a pic of everything already installed. While here 4 new fuses and also bypass caps for the filtering cans. Next is the meter board Edited February 23, 2016 by vintagejapan Link to comment Share on other sites More sharing options...
walker1000 Posted February 23, 2016 Share Posted February 23, 2016 I cant believe how quickly your doing this, when I recapped my vintage radio it took me about a month, I was enjoying it so much that I took my time almost like I didnt want to finish it if that makes any sense. Link to comment Share on other sites More sharing options...
craigl Posted February 23, 2016 Share Posted February 23, 2016 (edited) May I be so bold to ask, "is this one mine" ? Edited February 23, 2016 by craigl 1 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 23, 2016 Author Share Posted February 23, 2016 May I be so bold to ask, "is this one mine" ? :-) Link to comment Share on other sites More sharing options...
vintagejapan Posted February 23, 2016 Author Share Posted February 23, 2016 I cant believe how quickly your doing this, when I recapped my vintage radio it took me about a month, I was enjoying it so much that I took my time almost like I didnt want to finish it if that makes any sense. This is my 4th one. And I do want to finish this by the end of next week. The case will be ready by then Link to comment Share on other sites More sharing options...
JPete9 Posted February 24, 2016 Share Posted February 24, 2016 (edited) Do you have B2 on ebay for around 1900? Edited February 24, 2016 by JPete9 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 24, 2016 Author Share Posted February 24, 2016 Do you have B2 on ebay for around 1900? ? no. But if you are interested let me know. Link to comment Share on other sites More sharing options...
vintagejapan Posted February 25, 2016 Author Share Posted February 25, 2016 Better speaker cable installed in the PS board All solder joints redone in the PS board and then cleaned up. Also redone all the wire connections to the PS board Link to comment Share on other sites More sharing options...
vintagejapan Posted February 25, 2016 Author Share Posted February 25, 2016 Next the meter board, lots of 2SC458 transistors here that need replacement. I used 2SC1518 Y and GR grade. Technology has progressed since the 70's Look at the size difference in the capacitor, same specs Old transistors from meter board. Most out of specs Meter board done. All cleaned up and ready to go. When installing the foil piece that covers the meter IC's cover the foil part with some isolating plastic, sometime it bends and can touch the driver board with bad consequences ... Link to comment Share on other sites More sharing options...
JPete9 Posted February 26, 2016 Share Posted February 26, 2016 ? no. But if you are interested let me know. Thanks...but out of my league financially i think...payment plan? 1 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 26, 2016 Author Share Posted February 26, 2016 Next we tackle the RCA selection board and the volume board. This are the Achilles heel for the B-2. I have come across of units that will not even produce sound if this switches are dirty. You need to take your time, Deoxit liquid or spray is highly recommended to clean them. Some people just spray them but to clean all the 30 year dirt and whathaveyou, you need to open them up. 1 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 26, 2016 Author Share Posted February 26, 2016 Thanks...but out of my league financially i think...payment plan? Sure, we can sort something out. 2 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 26, 2016 Author Share Posted February 26, 2016 Ok, next the most important stuff. The V-fets. I will install them using SIL-pads from Bergquist. Make sure to not mess up the position of the V-fets. I usually mark them, sometimes the rating is written on the back. Give them a good polish, they always sound "better" after that.. 1 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 26, 2016 Author Share Posted February 26, 2016 Since everything is in we can power up the amp for the first time. Lights are ON, and then that sweet sound of the relay "Clang" Make sure bias pot is at 0 when powering up for the first time. After 10 min or so I was able to dial up 40mV on the bias and about 2mV on the DC balance. Still more to do but signing off till monday! Case will be ready and the rest of installation can be completed 4 Link to comment Share on other sites More sharing options...
analog brother Posted February 27, 2016 Share Posted February 27, 2016 that multi-meter is a classic now. 2 Link to comment Share on other sites More sharing options...
vintagejapan Posted February 27, 2016 Author Share Posted February 27, 2016 that multi-meter is a classic now. Sure has travelled a lot! Link to comment Share on other sites More sharing options...
betocool Posted February 27, 2016 Share Posted February 27, 2016 What do you use to clean the back of the boards? Link to comment Share on other sites More sharing options...
vintagejapan Posted February 27, 2016 Author Share Posted February 27, 2016 (edited) What do you use to clean the back of the boards?I am sure you will find lots of option, in Japan I use this stuff Edited February 27, 2016 by vintagejapan Link to comment Share on other sites More sharing options...
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