Ok thanks will doizzy wizzy wrote: ↑Sat Aug 24, 2019 5:15 pm Check the value of the 47k resistor feeding the 100u capacitor. If it was low or has been shorted via a solder blob, the cap will charge up stright away rather than following slowly.
DHT Heater using VCCS - PCB or Kit (Possible Group buy)
#1096 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
#1097 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Also check the 470k resistors and the 470nF caps.
Analogue, the lost world that lies between 0 and 1.
#1098 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Thanks. Work has dragged me away from hifi I'm afraid. I'll check later this week.
- izzy wizzy
- Old Hand
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#1099 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
It's been a while since I heatsinked anything.
For higher currents, I have a finned heatsink. I have silicon isolation tabs which I believe don't need thermal compound stuff like the old mica ones did from memory. I don't have heatsink compound.
Can I get away without the compound at all; devices straigh to sink? Would it be better to use the silicon tabs even though I don't need them isolated?
Cheers,
Stephen
For higher currents, I have a finned heatsink. I have silicon isolation tabs which I believe don't need thermal compound stuff like the old mica ones did from memory. I don't have heatsink compound.
Can I get away without the compound at all; devices straigh to sink? Would it be better to use the silicon tabs even though I don't need them isolated?
Cheers,
Stephen
#1100 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
I think you're right that the silicon type don't need compound, but the datasheet will tell you.
If you need it I have 2 spare syringes of compound, happy to send you some, no idea why I bought three.
If you need it I have 2 spare syringes of compound, happy to send you some, no idea why I bought three.
- izzy wizzy
- Old Hand
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- Joined: Fri Nov 02, 2007 7:02 pm
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#1101 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Your reply prompted me to know what to look for. I thought I had the compound in a tub and couldn't find it but you saying syringe made me go look in the shed and bingo, found syringe of the stuff. Sorted thank you.
Cheers,
Stephen
Cheers,
Stephen
#1102 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Lol glad I could help
- IslandPink
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#1103 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Phew !
I was fearing your room would be full of the smell of magic smoke, for a while there.
I was fearing your room would be full of the smell of magic smoke, for a while there.
"Once you find out ... the Circumstances ; then you can go out"
#1104 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Hi Andrew, I am new here, would like to know if the board still available, please. Will use it for 300B single. Thanks.
#1105 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Yes, one PCB is suitable for a single 300B, I have spare PCB. It sounds like you need a pair?
Analogue, the lost world that lies between 0 and 1.
#1106 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Yes, please PM me so we can discuss payment process, etc. Thank you.
#1107 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Not a direction you'll regret, Andrews DHT supplies are excellent.
Sorry, I couldn't resist!
#1108 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
Thanks Ray P I would need your help for advice..
#1109 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)
PM sent
Analogue, the lost world that lies between 0 and 1.