Hi guys,
Looking for help confirming PT connections for a TSE board running 45 tubes, i got an ISO Tango power tranny that is less obvious with its heater connections, centre taps and v ratings, the tranny in the same as the one in the attached picture.
So:
T1 RED 1 & 3 - HV 280v taps
T1 RED YEL 2 - HV centre tap (0)
T1 YEL 1 - 5v 1 tap
T1 YEL 3 - 5v 0 tap
T1 GRN 1 - 6.3v 1 tap
T1 GRN 2 - 6.3v 0 tap
Many thanks
J
Looking for help confirming PT connections for a TSE board running 45 tubes, i got an ISO Tango power tranny that is less obvious with its heater connections, centre taps and v ratings, the tranny in the same as the one in the attached picture.
So:
T1 RED 1 & 3 - HV 280v taps
T1 RED YEL 2 - HV centre tap (0)
T1 YEL 1 - 5v 1 tap
T1 YEL 3 - 5v 0 tap
T1 GRN 1 - 6.3v 1 tap
T1 GRN 2 - 6.3v 0 tap
Many thanks
J
I'm no expert here so best to wait for others to chime in, but AFAIK you need a CT for the 6.3V winding for 45's. Maybe with some other modification you can make it work without a CT.
The 300B doesn't require a CT on the 6.3V tap, so that is one other option if you prefer to stay with this PT (using the 320V HV winding, and bias around 60mA)
The 300B doesn't require a CT on the 6.3V tap, so that is one other option if you prefer to stay with this PT (using the 320V HV winding, and bias around 60mA)
@ itsikhefez - thanks for the input, so i am naturally now leaning towards 300b, i had read that the regulator chip could handle the extra hit without the CT but it is easy to find any answer we desire on the interweb : )) luckily i already have a nice pair of the Psvane ACME 300bs to apply, proof of excellent concept of the TSE - new paths are always available if needed!
Good luck! I'm not sure whether you have already built the board with 45's in mind, but there are small modifications for the 300B, such as:
1) The jumper (pad3-pad4 for 5V)
2) R6 and R36 may need to be a higher wattage part depending on B+
3) R2 is 300R (for 5V)
4) D6 should be changed to the 200V part
5) Ensure your output transformers and choke are compatible
1) The jumper (pad3-pad4 for 5V)
2) R6 and R36 may need to be a higher wattage part depending on B+
3) R2 is 300R (for 5V)
4) D6 should be changed to the 200V part
5) Ensure your output transformers and choke are compatible
A basic difference is the 45 wants 2.5V for heater, 300b wants 5V and less current.
Theoretically, you could use the 6.3V 3A tap for the 45 heaters, but 3A is exactly what the 45's need, so there is no margin. I wouldn't recommend running an amp like this, I also make sure things are spec'ed higher then what I run them at. You would also have more heat to dissipate since the voltage to the reg would be much higher.
You also have those 2.5V taps, but they are probably a little too low voltage to get 2.5VDC regulated to the 45's.
So close.
Theoretically, you could use the 6.3V 3A tap for the 45 heaters, but 3A is exactly what the 45's need, so there is no margin. I wouldn't recommend running an amp like this, I also make sure things are spec'ed higher then what I run them at. You would also have more heat to dissipate since the voltage to the reg would be much higher.
You also have those 2.5V taps, but they are probably a little too low voltage to get 2.5VDC regulated to the 45's.
So close.
I'd worry a bit about electrical noise the fan induces.
I know people make cap filter boards for fan power, at least they used to, for PC's.
In my build, I used bigger heatsinks, but it was a fair amount of work. Mine may be overkill, and there is probably an easier way to do it than I did. ICs/transistors are mounted to an about 3/8 inch thick plate. Made tapped holes in the plate to mount the plate to the pcb. Then I screw the plate into a heatsink.
I know people make cap filter boards for fan power, at least they used to, for PC's.
In my build, I used bigger heatsinks, but it was a fair amount of work. Mine may be overkill, and there is probably an easier way to do it than I did. ICs/transistors are mounted to an about 3/8 inch thick plate. Made tapped holes in the plate to mount the plate to the pcb. Then I screw the plate into a heatsink.
Yes, that 5 volt fan would likely consume 100mA or more. The 70 volt tap is intended for half wave bias supply only, maybe 1 mA max.
Many of those don't live long. My PC is now on the operating table because both cheap plastic 5 volt fans seized up and quit spinning. Things obviously got hot inside, but the real reason for the operation is that all the hard drives are now 5 to 8 years old....bad stuff in eminent. You know how long it takes to back up 10 TB.....now on day three.
I have used decent quality 12 volt fans, and wired them to rectified and filtered 6.3V. This is 7 or 8 volts and makes the fans spin slow and quietly. You don't need or want a bunch of airflow, just some air movement so that the heat sinks can do their job.
I will make something eventually, but there are lots of detours on that road. The biggest is now my location. I live in a "holler" basically on a creek bed with 300+ foot hills all around me. There is no cell service here, no TV, and very little RF in general. Anything above 6 meters is silent except for a couple of weak repeaters on 2. I haven't put up an HF antenna yet, but it will probably be a wire dipole of some sort.
Awesome info as per usual guys, many thanks
Backing up hard drives is the stuff i imagine is lined up for those grafting in hell : ))
My thoughts going out to you G
[/QUOTE]I have used decent quality 12 volt fans, and wired them to rectified and filtered 6.3V. This is 7 or 8 volts and makes the fans spin slow and quietly. You don't need or want a bunch of airflow, just some air movement so that the heat sinks can do their job. [/QUOTE]
Sounds ideal. Where on the board would be the best place to connect a fan George, i assume the fan does not need grounding either?
Backing up hard drives is the stuff i imagine is lined up for those grafting in hell : ))
My thoughts going out to you G
[/QUOTE]I have used decent quality 12 volt fans, and wired them to rectified and filtered 6.3V. This is 7 or 8 volts and makes the fans spin slow and quietly. You don't need or want a bunch of airflow, just some air movement so that the heat sinks can do their job. [/QUOTE]
Sounds ideal. Where on the board would be the best place to connect a fan George, i assume the fan does not need grounding either?
You want the raw 7 to 8 volt supply. In a 300B amp the negative lead of the fan goes to ground, and the positive lead goes to the positive lead of C1. You can connect the fan right across C1.
In a 2A3 or 45 amp the positive lead still goes to the positive terminal of C1, but the negative lead goes to the negative terminal of C2.
If the fan has a metal frame, it should be grounded for safety, just because it's metal.
I have a large digital footprint. Over 4 TB is just pictures going back to 2003. These have been scattered across dozens of hard drives in dozens of computers. I bought a 10 TB drive and started backing up a stack of old hard drives and my three PC's. I have been at this for three days and am nowhere near done. The 10 TB drive now contains over 5 million files and 7 TB of data. After the current drive is copied I'll go back and delete any duplicates and defrag the drive....there are about 6 more drives to back up, but many of those files are duplicates.
In a 2A3 or 45 amp the positive lead still goes to the positive terminal of C1, but the negative lead goes to the negative terminal of C2.
If the fan has a metal frame, it should be grounded for safety, just because it's metal.
I have a large digital footprint. Over 4 TB is just pictures going back to 2003. These have been scattered across dozens of hard drives in dozens of computers. I bought a 10 TB drive and started backing up a stack of old hard drives and my three PC's. I have been at this for three days and am nowhere near done. The 10 TB drive now contains over 5 million files and 7 TB of data. After the current drive is copied I'll go back and delete any duplicates and defrag the drive....there are about 6 more drives to back up, but many of those files are duplicates.
Hi all - I'm about to start on my TSE-II build (300b) and wondering if the heat sinks listed in the BOM on page 1 are suitible for and under chassis mount, like having only tubes on top and the rest under the chassis? And also, does anyone know a source for a suitable insulator for IC1 and IC2? Many thanks!