DHT Heater using VCCS - PCB or Kit (Possible Group buy)

What people are working on at the moment
RhythMick
Old Hand
Posts: 747
Joined: Fri Jun 23, 2017 12:24 pm

#1096 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by RhythMick »

izzy 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.
Ok thanks will do
Andrew
Eternally single
Posts: 4206
Joined: Thu May 24, 2007 2:18 pm

#1097 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by Andrew »

Also check the 470k resistors and the 470nF caps.
Analogue, the lost world that lies between 0 and 1.
RhythMick
Old Hand
Posts: 747
Joined: Fri Jun 23, 2017 12:24 pm

#1098 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by RhythMick »

Thanks. Work has dragged me away from hifi I'm afraid. I'll check later this week.
User avatar
izzy wizzy
Old Hand
Posts: 1496
Joined: Fri Nov 02, 2007 7:02 pm
Location: Auckland NZ
Contact:

#1099 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by izzy wizzy »

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
RhythMick
Old Hand
Posts: 747
Joined: Fri Jun 23, 2017 12:24 pm

#1100 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by RhythMick »

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.
User avatar
izzy wizzy
Old Hand
Posts: 1496
Joined: Fri Nov 02, 2007 7:02 pm
Location: Auckland NZ
Contact:

#1101 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by izzy wizzy »

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
RhythMick
Old Hand
Posts: 747
Joined: Fri Jun 23, 2017 12:24 pm

#1102 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by RhythMick »

Lol glad I could help
User avatar
IslandPink
Amstrad Tower of Power
Posts: 10041
Joined: Tue May 29, 2007 7:01 pm
Location: Denbigh, N.Wales

#1103 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by IslandPink »

Phew !
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"
jc123
User
Posts: 6
Joined: Thu Mar 05, 2020 3:50 pm

#1104 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by jc123 »

Hi Andrew, I am new here, would like to know if the board still available, please. Will use it for 300B single. Thanks.
Andrew
Eternally single
Posts: 4206
Joined: Thu May 24, 2007 2:18 pm

#1105 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by Andrew »

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.
jc123
User
Posts: 6
Joined: Thu Mar 05, 2020 3:50 pm

#1106 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by jc123 »

Yes, please PM me so we can discuss payment process, etc. Thank you.
User avatar
Ray P
No idea why I do this anymore
Posts: 6294
Joined: Thu Nov 22, 2007 5:18 pm
Location: Somerset

#1107 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by Ray P »

jc123 wrote: Thu Mar 05, 2020 8:43 pm Hi Andrew, I am new here, would like to know if the board still available, please. Will use it for 300B single. Thanks.
Not a direction you'll regret, Andrews DHT supplies are excellent.
Sorry, I couldn't resist!
jc123
User
Posts: 6
Joined: Thu Mar 05, 2020 3:50 pm

#1108 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by jc123 »

Thanks Ray P I would need your help for advice.. :D :D
Andrew
Eternally single
Posts: 4206
Joined: Thu May 24, 2007 2:18 pm

#1109 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by Andrew »

PM sent :)
Analogue, the lost world that lies between 0 and 1.
jc123
User
Posts: 6
Joined: Thu Mar 05, 2020 3:50 pm

#1110 Re: DHT Heater using VCCS - PCB or Kit (Possible Group buy)

Post by jc123 »

Thank you.
Post Reply