There are many ways. For the time being use a crocodile clip to reg out gnd somewhere. Later when you will set it up for good, you will see to maybe earth psu gnd to chassis, and use a chassis point for TT gnd.
I do earth psu gnd to chassis, and use a chassis point for TT gnd.
Channel left sounds music but not clear like if was a kind of bad contact, the sounds is like a continous "hum".
Channel right don't sounds nothing, only sounds like a continous "hum" without music. I open the box to be sure about connections.
Channel left sounds music but not clear like if was a kind of bad contact, the sounds is like a continous "hum".
Channel right don't sounds nothing, only sounds like a continous "hum" without music. I open the box to be sure about connections.
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You will sort it out sooner or later. Those things as in your hands. If you will have any plausible data, like how it is connected to the cart, weird voltages etc. we can help.
I changed the dual LSK389 (Q2+Q5) & now I have music in channel right too, but now the noise is increased.
Will be possible due to the AC electricity inside the RIAA box or long cables between regs & RIAA or long cables between RIAA & RCA connectors?
Could help to reduce the noise doing "remote sensing" in the regs.?
Will be possible due to the AC electricity inside the RIAA box or long cables between regs & RIAA or long cables between RIAA & RCA connectors?
Could help to reduce the noise doing "remote sensing" in the regs.?
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I do a new measurement after change Q2 & Q5 in RIGHT channel the new values are as follows:
LEDs 7-7.3V
LEFT 7.35V
RIGHT 7.39V
How can reduce the voltage to optimal value 7-7.3V?
R17 voltage across
LEFT 345mV
RIGHT 338mV
Wich is the right or optimal value?
R10/Q2-GND
LEFT 10V
RIGHT 10V
That's OK both channels
R1/Q3-GND
LEFT 11,5V
RIGHT 41,6V
How can reduce it till right value 11.5V? with mine R1 trimmer only can reduce it till 39.2V, is possible Q3 (BC550C) is burned?
R7 voltage across
LEFT 10.14
RIGHT 10.13
That's Ok both channels but I if possible I want to kow the optimal value?
DRAIN Q5/GND
LEFT 21.4V
RIGHT 21.1V
That's Ok both channels but If possible I want to know the optimal value?
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All other values perfectly adequate. That 41.6V indicates no real current is drawn. Either the BC550C Q3 or the two paralleled fets underneath are dead.
Thks, 1st I will change the BC550C after will do a new measurement if wrong I will change also the paralleled njfets but only I have maximum one 9,74 Idss an the other one 9,72 Idss, could I use it.
The cemetery filling.🙁
The cemetery filling.🙁
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Yes you can, you have trimmer. About burning, well, you are new to total construction, thats how we learn. That's a good circuit to sharpen your teeth, imagine if it was a heavyweight 4 stages cyclotron valve amp with 500V B+.
Finally I used a lot of mine special R1 trimmer.🙂
Yes your phono is a easy way to start, I do because I see few pasive & active components, if was complicated sure I never started the project.
Bad news, double paralleled njfets has gone becase I changed BC550C & voltage follows the same😡 the only good thing is that don't need to solder only replace the LSK389
Yes your phono is a easy way to start, I do because I see few pasive & active components, if was complicated sure I never started the project.
Bad news, double paralleled njfets has gone becase I changed BC550C & voltage follows the same😡 the only good thing is that don't need to solder only replace the LSK389
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I'm asking in Salas low voltage shunt regulator thread if I can use a couple of these:
Primary 0-230V AC
Secondary 0-45V AC / 1.8A / 81VA
An externally hosted image should be here but it was not working when we last tested it.
Primary 0-230V AC
Secondary 0-45V AC / 1.8A / 81VA
I changed double njfet Q1+Q7 for a new one LSK389 9,74 Idss & 9,72 Idss, I checked & left the optimal voltages as recommended, so voltages both channels ok, channel right don't sound, less hum in Left channel due to the new configuration:
1 Tx + 1 PSU one box
1 Reg + 2 Phono RIAA other box
No I only have seven LSK389 on hand with the folowing Idss:
1 9,32+9,25
2 9,29+9,28
3 9,23+9,29
4 8,05+8,24
5 7,83+7,82
6 7,42+7,50
7 7,25+7,02
I am in mind changing the setup for SK170BL because I have a batch of one hundred.
Please help?
An externally hosted image should be here but it was not working when we last tested it.
1 Tx + 1 PSU one box
1 Reg + 2 Phono RIAA other box
No I only have seven LSK389 on hand with the folowing Idss:
1 9,32+9,25
2 9,29+9,28
3 9,23+9,29
4 8,05+8,24
5 7,83+7,82
6 7,42+7,50
7 7,25+7,02
I am in mind changing the setup for SK170BL because I have a batch of one hundred.
Please help?
Since you got your bias voltages right, you have gone a long way. 1. Hum. Shielded coaxial cable for input and output. 2. One channel no sound. Exchange inputs, outputs to make sure it isn't something not giving or passing signal further in the rest of the system. Else see what connector or component in the audio path is missing a connection on the silent board. Use DVM in Ohm mode. Much better box and elements configuration by the way.
I don't understand nothing, I changed the RCA inputs from TT (so Left to Right & Right to left) & now both channels are singing?
Change again... sometimes phono plugs do not conduct signal due to corrosion.
Change cables if you can... just to be sure
Change cables if you can... just to be sure
I changed & the Right channel don't sound, I changed to reverse & both channels sound. 2nd time changed again & right channel don't sound, reversed & both channels sound. 3rd time connected left to left & right to right & both sounds finally ok. Seems like inside the phono RIAA the connections are reversed, I will open to be sure & will change the cables for coaxials as kind advice of Salas.
The TT cables or the cables between Phono & Preamp are right, due to the fact that are the same I used between the TT Piccolo MC HeadAmp from Jim Hagerman & MM Rotel several months without any kind of problem. The TT cables are the originals Linn, the cable between the Piccolo & the MM Rotel is this:
The TT cables or the cables between Phono & Preamp are right, due to the fact that are the same I used between the TT Piccolo MC HeadAmp from Jim Hagerman & MM Rotel several months without any kind of problem. The TT cables are the originals Linn, the cable between the Piccolo & the MM Rotel is this:
An externally hosted image should be here but it was not working when we last tested it.
I forget to tell an important subjective opinion: the Salas Phono NJFET RIAA + Shunt Reg. sounds very natural, open, very equilibrated (don't sound more the bass, or the mids or the trebles), now I go fast to change the cables for other coaxials to avoid hum.
Mine first vinyl to listen:
Mine first vinyl to listen:
An externally hosted image should be here but it was not working when we last tested it.
