Are there any tubes in the board? Do you have a switch or jumper across the SW 1 terminals? If there are no tubes, and a jumper (or closed switch) your readings seem OK. The transformer voltage will be high with no load, so will the B+.
I would recommend removing the jumper, or opening (off) the switch for initial testing. The voltage at the yellow wires should be low or zero without tubes.
With all tubes in place the voltage at the yellow wires should be 430 to 480 volts.
I would recommend removing the jumper, or opening (off) the switch for initial testing. The voltage at the yellow wires should be low or zero without tubes.
With all tubes in place the voltage at the yellow wires should be 430 to 480 volts.
OK - Brain fart time...I spent 18 hours in the air yesterday so I am still not thinking clearly.... 
No tubes, no jumper
yel 1 - 5.1
yel 2 - 0
red 1 415
red 2 415
red/yel - 0
green/yel - 2.3
green 1 - 6.3
green 2 - 0
With tubes and jumper
yel 1 - 547
yel 2 - 547
red 1 - 409
red 2 - 409
red/yel - 0
green/yel - 75
green 1 - 76
green 2 - 76
wall voltage today is 122.1
Thinking this through again, this now seems to make sense to me with no load...
One thing still eludes me...what is the purpose of the red/yel tap? after I got 0 volts in both situations I took an OHM reading and it read 0...
Thanks,
(sleepy) Carl
No tubes, no jumper
yel 1 - 5.1
yel 2 - 0
red 1 415
red 2 415
red/yel - 0
green/yel - 2.3
green 1 - 6.3
green 2 - 0
With tubes and jumper
yel 1 - 547
yel 2 - 547
red 1 - 409
red 2 - 409
red/yel - 0
green/yel - 75
green 1 - 76
green 2 - 76
wall voltage today is 122.1
Thinking this through again, this now seems to make sense to me with no load...
One thing still eludes me...what is the purpose of the red/yel tap? after I got 0 volts in both situations I took an OHM reading and it read 0...
Thanks,
(sleepy) Carl
It is the center tap on the high voltage winding and it is connected to ground therefore it should read zero ohms to ground.
547 volts sounds too high if the output tubes are in place. Check the voltages at the end of R17 and R27 that is closest to the rear of the PC board. It should be about 30 volts depending on the output tube used.
Please do not play with electricity if you are not totally alert. 547 volts can really ruin your day. I routinely cease my experimentation at 10 PM since I know I am not as alert after 10, and I have been doing this for 40 years.
George, you are 100% correct. I have called it a day.
I did take one last reading across R17 and R27 and there is zero volts indicated. I guess I have a cold solder joint somewhere upstream...there is also zero volts on R18 and R28...
Would there be a common culprit for this symptom?
I will put off trying to trace it down till tomorrow when I am of more sound mind...
I did take one last reading across R17 and R27 and there is zero volts indicated. I guess I have a cold solder joint somewhere upstream...there is also zero volts on R18 and R28...
Would there be a common culprit for this symptom?
I will put off trying to trace it down till tomorrow when I am of more sound mind...
This indicates that the B+ is not getting to the output tubes. Are the OPT's in place and connected correctly? If you are using triode mode, do you have the jumper between the right most terminals of the OPT connector?
Check for voltage on all three terminals of the T3-PRI connector. You already indicate that there is no voltage or R28 which is the center terminal. There should be voltage on the left terminal since it comes through the board. There should be voltage on the right terminal. It comes through the OPT. If there is no voltage, check the OPT wiring. The center terminal gets powered through the OPT in UL mode. It should be jumpered to the right terminal in triode mode.
T2-PRI works the same way.
Ty_Bower said:
The JJ ecc99 is doing great in my amp driving 6550s. I set the ccs current resistor at 150 Ohms so its running at 22 mA or so plate current. I haven't measured it (or anything else) yet... just been using it every day for the last few months
The JJ ecc99 was designed specifically as an audio power tube driver, and it is a very linear tube with a much lower mu than a 12at7.
Dave
OK, after a couple of weeks of other projects taking priority I have finally done a test run with the Simple SE...
All I can say is WOW...it is dead silent. Now it is not as "loud" as the yamaha CA-810 but when I run it through the CA-810 acting as a pre-amp the Simple SE really shines.
I am running the cheap chinese 6L6GC tubes...I am really excited to try some KT88's...or mayber some EL34's...
I have been listening to the Simple SE through the Yamaha CA-810 as pre-amp and Technics SL-1300 Genesis - The Lamb Lies Down on Broadway and it sounds really nice...maybe the best descriptive word is "genuine"...
very impressed with the Simple SE...
Carl
All I can say is WOW...it is dead silent. Now it is not as "loud" as the yamaha CA-810 but when I run it through the CA-810 acting as a pre-amp the Simple SE really shines.
I am running the cheap chinese 6L6GC tubes...I am really excited to try some KT88's...or mayber some EL34's...
I have been listening to the Simple SE through the Yamaha CA-810 as pre-amp and Technics SL-1300 Genesis - The Lamb Lies Down on Broadway and it sounds really nice...maybe the best descriptive word is "genuine"...
very impressed with the Simple SE...
Carl
I still have to finish the base cabinet so no pics yet...
The 6L6GC's have a great sound. I sampled a little rock, electronic, and downtempo/chill from my ipod and it all sounded really warm. I was picking out sounds that I have never heard from my car stereo or my home theater receiver.
I cant wait to get the chassis finished!
The 6L6GC's have a great sound. I sampled a little rock, electronic, and downtempo/chill from my ipod and it all sounded really warm. I was picking out sounds that I have never heard from my car stereo or my home theater receiver.
I cant wait to get the chassis finished!
I liked the record so much that I bought the CD. Now I play the record again, yes I still have it. And Trick of the Tail, and Selling England by the Pound, and , and Foxtrot, and Seconds Out and Genesis Live (blue cover). Good stuff.
I also have a record called From Genesis to Revelation dated 1969. It has a paper liner with an explanation as to why the group was changing their name to Revelation in America. It features Peter Gabriel, Tony Banks, and Mike Rutherford, no Phil Collins.
Update!!!
I put a chassis together out of poplar and some brass screws and washers - came out pretty nice.
I have it hard wired for UL with cathode feedback for now...I must say that it reallly sounds awesome.
I was not sure before if it could keep up with my yamaha CA-810 amp but I think it could give it a run for the money. I will really have to crank it up sometime when the wife is not directly upstairs trying to get the girls in bed...
Thanks again for all the feedback and ideas. I am very pleased with my first DIY audio project and glad I picked the Simple SE amp to do it with. Very painless process...
Last I measured I was getting about 465 B+ with that Allied 6K7VG...not bad...
I still need to add the triode/UL switch and CFB switch, power switch, and fuse. Also I will sand and finish the cabinet. I also got a honkin run cap that I will probably mount on the underside at some point...
Regards,
Carl
I put a chassis together out of poplar and some brass screws and washers - came out pretty nice.
I have it hard wired for UL with cathode feedback for now...I must say that it reallly sounds awesome.
I was not sure before if it could keep up with my yamaha CA-810 amp but I think it could give it a run for the money. I will really have to crank it up sometime when the wife is not directly upstairs trying to get the girls in bed...
Thanks again for all the feedback and ideas. I am very pleased with my first DIY audio project and glad I picked the Simple SE amp to do it with. Very painless process...
Last I measured I was getting about 465 B+ with that Allied 6K7VG...not bad...
I still need to add the triode/UL switch and CFB switch, power switch, and fuse. Also I will sand and finish the cabinet. I also got a honkin run cap that I will probably mount on the underside at some point...
Regards,
Carl
If you don't hear hum with your speakers, don't worry about it. If you get some super efficient speakers in the future, you may need to change it.
My original Tubelab SE amp (top picture on my home page) has all 3 transformers lined up in a row, which is pretty much worse case. There was no hum with my 87 db Yamaha speakers which have a limited low frequency response. When I got some bigger speakers with 96 db efficiency and 15 inch woofers, HUM happened and I rotated the power transformer 90 degrees.
cjkpkg said:
If it's not humming I would not worry about it either, but if it really bugs you, you can use an epoxy filler to fill the extra holes, and then sand it and paint (or not) the chassis.
I am sympathetic to the Swiss Cheese syndrome. My Simple SE started its life on a chassis that was once my first homebrew SSB transceiver. Then I burned up my first power transformer, a choke, and have tried a variety of output transformers on it. It was to the point it almost had more holes than chassis.
Once I had my Tubelab SE up and running, I decided the Simple SE had earned an overhaul, so I stripped it down to bare metal, epoxy filled the extra holes, and sanded and sprayed some new paint on it.
It doesn't look as good as a fresh chassis, but it's not bad.
Nice amp by the way!
Win W5JAG
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