Apologies if this isn't the correct location, but since I'm building an F6..... Someone mentioned using a (from memory) a cl30 thermistor it seemed in place of a soft start to prevent blowing a fuse at power up. Acceptable? Thoughts?
Cl 60 , is the good type of thermistor , get there and you'll have the all story :
F6 Illustrated Build Guide
.
F6 Illustrated Build Guide
.
Thank you for the quick reply, I've looked at the build guide plenty and never noticed the thermistor on chassis ground before, duh. I have them, but with chassis on order, want to dot the i's, don't like surprises.
That's the audio ground lift, there to raise signal ground off the chassis by the cold resistance of the thermistor.

Can I check if this is a correct way to use thermistors and x1/x2 rated cap for two separate transformers with single 240V primaries?

Last edited:
Personally I would just use one thermistor.
If one fails it leaves power on the other side of the amp and this might cause problems.
If one fails it leaves power on the other side of the amp and this might cause problems.
Can I check if this is a correct way to use thermistors and x1/x2 rated cap for two separate transformers with single 240V primaries?
![]()
though, you need to have dedicated fuse for each xformer
Personally I would just use one thermistor.
If one fails it leaves power on the other side of the amp and this might cause problems.
I am unsure what is meant by the "other side" but a failed thermistor will
not cause a situation where there is only one polarity in the supply,
rather it will shift the load to the remaining thermistor and transformer
winding.
bummer!
goal is to have bipolar supply in the end !
which I didn't get from start
that calls for one common NTC and one common fuse, for both xformers
silly ZM
goal is to have bipolar supply in the end !
which I didn't get from start

that calls for one common NTC and one common fuse, for both xformers
silly ZM
CL60 is good enough for 320VA at 230Vac
however, boys lately discovered some other types, slightly better than CL60 regarding dynamic behavior during startup, but I can't remember in which thread to look for
anyway, CL60 works for sure
however, boys lately discovered some other types, slightly better than CL60 regarding dynamic behavior during startup, but I can't remember in which thread to look for
anyway, CL60 works for sure
Great thanks again. Yikes I posted the previous reply without checking the thread and everyone else chimed in already, so thanks everyone.
May be this one....CL60 is good enough for 320VA at 230Vac
however, boys lately discovered some other types, slightly better than CL60 regarding dynamic behavior during startup, but I can't remember in which thread to look for
anyway, CL60 works for sure
https://www.tdk-electronics.tdk.com/inf/70/db/var/SIOV_Leaded_AdvanceD.pdf
goal is to have bipolar supply in the end !
which I didn't get from start
that calls for one common NTC and one common fuse, for both xformers
silly ZM
Silly me, I thought that was one transformer.....

Silly me, I thought that was one transformer.....
![]()
That's my Pa ........
🙂
Thanks Hicoco!
Which of the TDK part numbers would you recommend for a 240V power supply where CL60 is normally used?
What would be the improvement over CL60?
This one is for 275V B72220S2271K101Thanks Hicoco!
Which of the TDK part numbers would you recommend for a 240V power supply where CL60 is normally used?
What would be the improvement over CL60?
- Home
- Amplifiers
- Pass Labs
- Thermistor