Hi. I almost completed my Mesmerize and just a few questions:
What IDSS current do you recommend for the B1 matched quad 2SK170BL?
I have a great range I can choose from from about 6.34 to 10.50ma
Is it necessary to match some of the Shunt Reg 2SK170 FET, or I can use any IDSS current I want? Match per section, per side, etc...
What is the Led Vforward I need to match for the LED used in the Shunt Reg section? Is it 1.8V? What circuit do you use to match them, serie resistor, supply voltage, etc? Or do you match them into the circuit?
I don't have the BC517 (Darlington NPN transistor) use for the relay drive. Can I use some other transistor, is it necessary to have a darlington there?
I have BC550, BC547, BD139, BDX53C, MPSA06, ZTX450 (all NPN, but I also have their complement as well) in stock. Any of these could do the job?
Thanks in advance.
SB
What IDSS current do you recommend for the B1 matched quad 2SK170BL?
I have a great range I can choose from from about 6.34 to 10.50ma
Is it necessary to match some of the Shunt Reg 2SK170 FET, or I can use any IDSS current I want? Match per section, per side, etc...
What is the Led Vforward I need to match for the LED used in the Shunt Reg section? Is it 1.8V? What circuit do you use to match them, serie resistor, supply voltage, etc? Or do you match them into the circuit?
I don't have the BC517 (Darlington NPN transistor) use for the relay drive. Can I use some other transistor, is it necessary to have a darlington there?
I have BC550, BC547, BD139, BDX53C, MPSA06, ZTX450 (all NPN, but I also have their complement as well) in stock. Any of these could do the job?
Thanks in advance.
SB
7-10mA will do. Whatever you have plenty. Normally around 8-8.5 most matches occur.
You can match those under the 5 string leds that see ground through 10Rs. The others no. Use what does not match mostly so to utilize.
1.8Vf are mostly ok. 1k resistor and a 9V battery.
You can use BC550. If you experience relay chatter, it happens sometimes with just NPNs, use a Miller cap of 100-150n between B,C of the coil driver NPN. BC517 does not present that problem with any relay.
Hi all,
may I ask 2 basic questions?
1) Do I have just parallell the inputs RCAs for a tape-loop output?
2) Nobody has already tested Sowter 3575 trafo for bal ins and outs?
Thanks
may I ask 2 basic questions?
1) Do I have just parallell the inputs RCAs for a tape-loop output?
2) Nobody has already tested Sowter 3575 trafo for bal ins and outs?
Thanks
hi all i've ordered a pr of hypnotise boards,i would like to to build a balanced pair,what if any, parts would i change todo this and what values would they change to,thanks in advance..
Never done it. But I think its a matter of connecting them up right to the XLRs than changing anything in the design.
Hi all,
may I ask 2 basic questions?
1) Do I have just parallell the inputs RCAs for a tape-loop output?
2) Nobody has already tested Sowter 3575 trafo for bal ins and outs?
Thanks
1. Yes. It would be better to parallel the output, since you would buffer your source that way, but that would be affected by volume control. Depends if you wanna listen normally when you record and tweak volume along.
2. I haven't heard of anybody having done that yet.
I have finally complete all the components soldering for DCB1. Now still waiting for Alps 20k volume pot from RS components, and source for chassis for it.
1. Main supply rail: +10.64V and -9.67V
2. Volt. drop across 68//68 : 1.613V and 1.750V
3. DC offset: R= 1mA and L= -2mA
May i know i there anything wrong with my DCB1?
Thanks.
Now still waiting for Alps 20k volume pot from RS components, and source for chassis for it. 1. Main supply rail: +10.64V and -9.67V
2. Volt. drop across 68//68 : 1.613V and 1.750V
3. DC offset: R= 1mA and L= -2mA
May i know i there anything wrong with my DCB1?
Thanks.
Attachments
Hi,
the 68//68 with just 1.6V across it is passing just 47mA through the CCS.
The two B1 stages may be taking Iq~8+8mA, the shunt circuit could be taking 12mA. That leaves just 19mA passing through the shunt FET.
That may be a bit low.
Experiment with adding a further 68r to make three in parallel and maybe a fourth 68r in parallel. Each 68r passes ~24mA through the CCS.
the 68//68 with just 1.6V across it is passing just 47mA through the CCS.
The two B1 stages may be taking Iq~8+8mA, the shunt circuit could be taking 12mA. That leaves just 19mA passing through the shunt FET.
That may be a bit low.
Experiment with adding a further 68r to make three in parallel and maybe a fourth 68r in parallel. Each 68r passes ~24mA through the CCS.
Will try adding more 68R in parallel to it, once I received Alps 20k volume pot from RS. Will report back back the out come. Right now can I test DCB1 without the volume pot? connect to my system Cambridge audio C840 CDP and Mcintosh MC240 power-amp driving JBL 4310. Because Mcintosh MC240 input come with volume control.