Soft start + switch on PCB - Page 2

Dante · 21st April 2007, 06:00 AM

Hi to all diyaudio folks,

This is my first post on diyaudio. Lots of great stuff.

Hello smithy666, your circuit seems great. I'm very interested in your soft-start circuit, but I need a 120 / 240 volts version.
Can you accept to send me the schematics. This way I will be able to modify and adapt it to my needs.

Thanks

AL

peranders · 21st April 2007, 06:41 AM

The transformer which is used has 2 x 115 VAC primary. Not so hard to change to 120 VAC in. Nice work by the way

Dante · 23rd April 2007, 10:38 PM

Hi,

Did you have any price idea for the three possible ways for your circuit ?

thanks,

AL

smithy666 · 23rd April 2007, 11:51 PM

Hi Dante
I haven't got a schematic in a form that I can easily post at this stage, but I will get around to it (another thing on the list...).
The bare PCBs I can do for US$20 each. I'll work out today the price for all the parts & PCB, and then also fully assembled and get back to you.
P-A is correct - the transformer has dual 110V primaries, so you would need to cut a track and parallel the windings. One other change is necessary - you would need to change a couple of compnent values in the voltage divider section for the soft start, but that would be straightforward.

Luke · 24th April 2007, 02:26 AM

Hi Smithy,

Whats the spacings of the transformer, will a jaycar one fit?

cheers ab

smithy666 · 24th April 2007, 03:27 AM

Hi ab
Not sure. Dimensions of the Block FL6/6 are 53x44. Datasheet with pinouts etc are here http://docs-asia.electrocomponents.c...6b8002776f.pdf
The Block FL6/6 is available from RS Components for about A$25 - probably not much different to the price of the Jaycar one. The heatsink I used was from Jaycar. The relays are RTB34012F (Digikey PB362-ND) and RTB34024F (Digikey PB363-ND), about US$3.40 a piece. You might be able to find another replacement for these as well, but I chose them as they are rated at 12A/3000VA. Everything else is pretty bog standard and can be sourced from Jaycar.

Dante · 24th April 2007, 06:17 AM

Hi Smithy66,

What is the other parts I need to change for a 120 volt version ?

If I use a push button and I have a power down,
how your circuit will react ?

Thanks,

AL

smithy666 · 24th April 2007, 08:06 AM

Hi AL
You need to change the mains cap from 0.33uF to 0.68uF, assuming 110V/60Hz (if my calcs are correct), to drop the correct voltage, which in your case is about 80V. This must be a mains rated cap (X1/X2). I used a Vishay MKP 338 series X1 cap (Digikey BC1595-ND for the 0.33uF).

If the power is lost, the relay is no longer energised, so defaults to the off position. When the power returns it is still in the off position until you press the on switch again (ie it is not latching - the coil is energised while the amp is "on")

Dante · 1st May 2007, 04:52 PM

I would be interested for one unit.

Any idea when it will be available ?

Loboone · 18th May 2007, 03:55 AM

Hi Smithy,

I am very interested in your boards. (230volt ac)

Do I need one per channel or will it do both channels of power amp?

Have you got pricing for boards only yet and delivery times etc?

Regards

Ian

21st April 2007, 06:41 AM	#12
peranders Electrons are yellow and more is better! diyAudio Member Join Date: Apr 2002 Location: Göteborg, Sweden Blog Entries: 4	The transformer which is used has 2 x 115 VAC primary. Not so hard to change to 120 VAC in. Nice work by the way __________________ /Per-Anders (my first name) or P-A as my friends call me Tube Buffered Gainclone in work \|Thread

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21st April 2007, 06:00 AM	#11
Dante diyAudio Member Join Date: Aug 2005	Hi to all diyaudio folks, This is my first post on diyaudio. Lots of great stuff. Hello smithy666, your circuit seems great. I'm very interested in your soft-start circuit, but I need a 120 / 240 volts version. Can you accept to send me the schematics. This way I will be able to modify and adapt it to my needs. Thanks AL

23rd April 2007, 10:38 PM	#13
Dante diyAudio Member Join Date: Aug 2005	Hi, Did you have any price idea for the three possible ways for your circuit ? thanks, AL

23rd April 2007, 11:51 PM	#14
smithy666 diyAudio Member Join Date: Mar 2001 Location: Sydney	Hi Dante I haven't got a schematic in a form that I can easily post at this stage, but I will get around to it (another thing on the list...). The bare PCBs I can do for US$20 each. I'll work out today the price for all the parts & PCB, and then also fully assembled and get back to you. P-A is correct - the transformer has dual 110V primaries, so you would need to cut a track and parallel the windings. One other change is necessary - you would need to change a couple of compnent values in the voltage divider section for the soft start, but that would be straightforward.

24th April 2007, 02:26 AM	#15
Luke diyAudio Member Join Date: Sep 2001 Location: Wellington NZ	Hi Smithy, Whats the spacings of the transformer, will a jaycar one fit? cheers ab

24th April 2007, 03:27 AM	#16
smithy666 diyAudio Member Join Date: Mar 2001 Location: Sydney	Hi ab Not sure. Dimensions of the Block FL6/6 are 53x44. Datasheet with pinouts etc are here http://docs-asia.electrocomponents.c...6b8002776f.pdf The Block FL6/6 is available from RS Components for about A$25 - probably not much different to the price of the Jaycar one. The heatsink I used was from Jaycar. The relays are RTB34012F (Digikey PB362-ND) and RTB34024F (Digikey PB363-ND), about US$3.40 a piece. You might be able to find another replacement for these as well, but I chose them as they are rated at 12A/3000VA. Everything else is pretty bog standard and can be sourced from Jaycar.

24th April 2007, 06:17 AM	#17
Dante diyAudio Member Join Date: Aug 2005	Hi Smithy66, What is the other parts I need to change for a 120 volt version ? If I use a push button and I have a power down, how your circuit will react ? Thanks, AL

24th April 2007, 08:06 AM	#18
smithy666 diyAudio Member Join Date: Mar 2001 Location: Sydney	Hi AL You need to change the mains cap from 0.33uF to 0.68uF, assuming 110V/60Hz (if my calcs are correct), to drop the correct voltage, which in your case is about 80V. This must be a mains rated cap (X1/X2). I used a Vishay MKP 338 series X1 cap (Digikey BC1595-ND for the 0.33uF). If the power is lost, the relay is no longer energised, so defaults to the off position. When the power returns it is still in the off position until you press the on switch again (ie it is not latching - the coil is energised while the amp is "on")

1st May 2007, 04:52 PM	#19
Dante diyAudio Member Join Date: Aug 2005	I would be interested for one unit. Any idea when it will be available ?

18th May 2007, 03:55 AM	#20
Loboone diyAudio Member Join Date: May 2005 Location: Hamilton Waikato NZ	Hi Smithy, I am very interested in your boards. (230volt ac) Do I need one per channel or will it do both channels of power amp? Have you got pricing for boards only yet and delivery times etc? Regards Ian