An output cap on the source, or an input cap on the receiver, is a safety measure to help prevent damge to speakers. Note I say "or". The Source and Receiver do not need both. One, or other, with the ability to bypass one when both are fitted.
If you omit the DC blocking capacitor on BOTH, then you should be looking at other safety measures to protect your speakers.
In my somewhat blinkered view, DC coupling requires at least DC detection and automated speaker isolation when the detection passes some preset threshold.
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Yes I think I will feel more comfortable with R12 in place before experimenting. Thanks.
I have only one source, a Sony CD player which most likely has output caps and which measures less than 2mv DC offset even at turn on.
Andrew, you refer to source or receiver. In my case the CD player will be connected to the BA3 FE to my F5TV3 monoblocks (no input or output caps here). By receiver do you mean the BA3FE in my instance?
Thanks.
the two ends of an interconnect see a source and a receiver.
move to the output side and use a different interconnect and what was the receiver becomes the source sending a signal to the next receiver in the chain.
A vol pot is both a source and a receiver. It should be designed to work well as a receiver when receiving a signal from another source and on the other side it should be designed to work well as a source when sending a signal to the next receiver, probably the power amp.
move to the output side and use a different interconnect and what was the receiver becomes the source sending a signal to the next receiver in the chain.
A vol pot is both a source and a receiver. It should be designed to work well as a receiver when receiving a signal from another source and on the other side it should be designed to work well as a source when sending a signal to the next receiver, probably the power amp.
After I posted last, I figured that this is what you probably meant. Thanks for confirming.
nash
Hi Gents, hoping for a little help with a recent SSLV1.1 BIB build; its been a while since i built these supplies and did any DIY so a little rusty! Some time ago i succesfully built 5 of them which have are working perfectly. I had a spare positive board and kit and tried to cobble together a 15v 1A supply for a network player from the parts i had to hand....i cant get it to work and have been creating smoke..
Am i right in assuming a BJT kit is capable of being configured as a 15v 1A supply using the supplied IRF9610 and MJE15030?
The voltage reference is configured with 2 red led @ 1.87v, diode position shorted a 2.3k resistor in R303 and a 200R trimmer in R305 - the calculator shows 66R being required at from the trimmer.
The calculator shows a value of 1.5R for 1200ma for R101 which is what i have in there.
1000uf electrolytic in C301 and 47uf film in C303.
When i power it up with a 1A dummy load i get no green leds lit D302-304 (4 leds fitted) and R301 immediately starts to burn up. All solder joints good, output from rectifiers 25VDC. Double checked all components values and positions etc.
Any pointers appreciated.
Am i right in assuming a BJT kit is capable of being configured as a 15v 1A supply using the supplied IRF9610 and MJE15030?
The voltage reference is configured with 2 red led @ 1.87v, diode position shorted a 2.3k resistor in R303 and a 200R trimmer in R305 - the calculator shows 66R being required at from the trimmer.
The calculator shows a value of 1.5R for 1200ma for R101 which is what i have in there.
1000uf electrolytic in C301 and 47uf film in C303.
When i power it up with a 1A dummy load i get no green leds lit D302-304 (4 leds fitted) and R301 immediately starts to burn up. All solder joints good, output from rectifiers 25VDC. Double checked all components values and positions etc.
Any pointers appreciated.
You need MJE15031 in a positive reg not 15030. At 1A is near its HFE droop area, just before. I would prefer a MOSFET output config at such current. But it does not seem to be the immediate problem, its it must be changed to proper PNP first. MJE15029 is as good too. The IRF9610 is abused at constant 1A though, look in its absolute max ratings chart, its 1A at case temperature of 100C i.e. it can do it but not for long lasting or surely stable unless the sinking is great, better use IRF9620 or IRF9520.
From the description the more suspicious thing seems like it is the CCS Mosfet is pulling much due to wrong output and the resistor sees the whole drop form input to output while allowing high current flow too due to its small value. After you restore the right output component, check if the MOSFET is still alive. Does it respond showing any VGS and heat, what is the voltage across R301 etc.
Something else looks like not working in the CCS again? Parts maybe got abused before. Is Q302 OK? Maybe open? The DMM in Ohms across it will show. Are the green LEDS checking alright and in same good orientation when blinking them with a 9V battery? No need to desolder for those checks.
From the description the more suspicious thing seems like it is the CCS Mosfet is pulling much due to wrong output and the resistor sees the whole drop form input to output while allowing high current flow too due to its small value. After you restore the right output component, check if the MOSFET is still alive. Does it respond showing any VGS and heat, what is the voltage across R301 etc.
Something else looks like not working in the CCS again? Parts maybe got abused before. Is Q302 OK? Maybe open? The DMM in Ohms across it will show. Are the green LEDS checking alright and in same good orientation when blinking them with a 9V battery? No need to desolder for those checks.
Salas thank you for the input, very much appreciated. I checked and it was the correct 15301 fitted, mistake in my post. I tested the led's in position as suggested and i had a failed green led, i replaced this and the regulator works perfectly.
I tested for a while under a 1A load and the IRF9610 is getting very even with good heat sinking as predicted, i will re- configure with mosfets and a new batch of same type led's.
Thanks for these great PSU's!
I tested for a while under a 1A load and the IRF9610 is getting very even with good heat sinking as predicted, i will re- configure with mosfets and a new batch of same type led's.
Thanks for these great PSU's!
Congrats for solving the issue1. Yes
2. Zobel first
3. R101 on four green ccs leds depends on your powerful Mosfet type of choice also. For IRFP9240 at 2.15A CCS it could be 1.5R 15-20W resistor to hold well. It will burn 7W constantly on itself.
4. You know that for no load 2.15A * 12V is going to burn on the output Mosfet and you also know that for 2A peak draw only 0.15A * 12V will burn there. What goes to amp and speakers you remove from output Mosfet power burned on the reg. Thats the key for any power level dissipation to solve. But there is also the CCS to think about cooling which always burns 2.15A * (Vin-Vout).
Very inefficient and even dangerously hot way to power a T amp. But you already know that
***
Being inefficient and even dangerously hot has been the way of my life.....and I am not a female even......
Salas,
I really like my T amp with my ME2, now with a 26 line amp (before a VT25A, and later may be your 6V6 line amp as my next project....if you are still using the 6V6 in your system now). They sing together well for me, and many of my friends.
My T amp is only being powered now by a very simple voltage regulated power supply unit with many caps.
Then I read in the Hypnotize as a general shunt reg. where Ian444 was building the reg. for his T amp; and in the simplistic-salas-low-voltage-shunt-reg....that Tham was building this reg. for his T amp......so I think I must build a sslv 1.1 for my T amp......and T amp powered in this manner sounds better than a 300B!!!!.......so here I am.
Salas, I am still slowly reading the two threats above (Salas' threats are always long and winding and interesting and practical).......appreciate if you could let me know if Ian444 and Tham reported back after they built the regs. please!!
****
Now back to my sslv1.1 board for my T amp:
1) I will try Sobel first....any suggestion on the parts to try first??
2) I am using IRF9530, what value of R101 please??
3) please also elaborate on "there is also the CCS to think about cooling which always burns 2.15A * (Vin-Vout).".....
Which transistor......and what I can do. to keep it cool...please...
4) if I need to go cooling with a fan......where is the best place I could take the power for the fan from.......I would imagine that it would be a DC fan.....
Thankyou so much.....
King
1. The same as in the SSLV manual.
2. You can never say exactly due to tolerances. I would be holding 1.8R and four greens to start.
3. I meant don't forget that the CCS MOSFET will dissipate too. If having 20V Raw DC and 13V regulated output at 2A setting, that would be 14W for instance. Never changing by the dynamic load draw. Its static, not like teh output MOSFET that shares its dissipation with the load.
4. 120mm DC fans are the quietest. Get a good PC fan from some computer store or online. Noctua and Noiseblocker are among the best.
2. You can never say exactly due to tolerances. I would be holding 1.8R and four greens to start.
3. I meant don't forget that the CCS MOSFET will dissipate too. If having 20V Raw DC and 13V regulated output at 2A setting, that would be 14W for instance. Never changing by the dynamic load draw. Its static, not like teh output MOSFET that shares its dissipation with the load.
4. 120mm DC fans are the quietest. Get a good PC fan from some computer store or online. Noctua and Noiseblocker are among the best.
Thankyou Salas,
For R101 I will start with 4 green LEDs and 1.8R @ 20-25W, and measure actual V across R101, and adjust to get +2.15A through it.
As to the DC fan, should I get a 24V DC 120mm fan, and take power from the C105 please??
Program to get some bottom line Rigol, Siglent, GW Instek etc. digital scope. Or some used classic cathode ray tube scope from Ebay, whatever you fancy. You are surely going to thank yourself for that many times in the future when so easier for solving situations in this hobby.
Since its a digital amp better use soft recovery diodes like MSR860G / MSRF860G
20000uF would be better at such constant current if it fits
Since its a digital amp better use soft recovery diodes like MSR860G / MSRF860G
20000uF would be better at such constant current if it fits
Thankyou Salas....I will be saving up for a scope.
And what about the minimum tube testing equipment??....I do not need to know the tube like I need to know my old parents.....I just like to know if the tube is good or need replacing....and may be to match a pair or a quad.....that all, unless you would suggest more.
And what about the minimum tube testing equipment??....I do not need to know the tube like I need to know my old parents.....I just like to know if the tube is good or need replacing....and may be to match a pair or a quad.....that all, unless you would suggest more.
Browse Ebay there are some modern affordable enough tube tester PCBs on offer. They still need some DIY to do in putting them together for wiring and housing. Look up "digital tube tester".
Don't use wires for C105, just look for snap in 20mF capacitors that fit the outer diameter available on the PCB. You should find some since you don't need high voltage models.
Don't use wires for C105, just look for snap in 20mF capacitors that fit the outer diameter available on the PCB. You should find some since you don't need high voltage models.
v1.2R parts
Hello,
New to the Salas topic, and the number of threads there are. I think this is a build-related question, but about v1.2 schematics, not v1.1 builds. Maybe this is not the right place to ask: if so, please pardon and point me in the right direction.
Have signed up for Teabag's 2016 buy of BIBLV regulator boards.
Question: the 1.2R schematics I found in another thread specify parts that are not readily available: 2N5459, 2SK170, IRF9240. I notice that along with the PCBs, I can also order a "minikit", which includes 2SK117, IFR9530, and other common stuff.
Are these parts substitutes for the harder to find parts specified in the schematic, or specifically:
(1) Can I use 2SK117 for Q3, Q4, Q8, Q9?
(2) Can I use IRF9530 for Q5
(3) Are there any other critical parts, in that substitutes need to be *really* close?
I am asking because I already have most of thee stuff in the minikit, and could save some money by just ordering the substitute parts mentioned above the next time I order Rs, Cs, heatsinks, solder wick, etc., from mouser.
Thank you.
Hello,
New to the Salas topic, and the number of threads there are. I think this is a build-related question, but about v1.2 schematics, not v1.1 builds. Maybe this is not the right place to ask: if so, please pardon and point me in the right direction.
Have signed up for Teabag's 2016 buy of BIBLV regulator boards.
Question: the 1.2R schematics I found in another thread specify parts that are not readily available: 2N5459, 2SK170, IRF9240. I notice that along with the PCBs, I can also order a "minikit", which includes 2SK117, IFR9530, and other common stuff.
Are these parts substitutes for the harder to find parts specified in the schematic, or specifically:
(1) Can I use 2SK117 for Q3, Q4, Q8, Q9?
(2) Can I use IRF9530 for Q5
(3) Are there any other critical parts, in that substitutes need to be *really* close?
I am asking because I already have most of thee stuff in the minikit, and could save some money by just ordering the substitute parts mentioned above the next time I order Rs, Cs, heatsinks, solder wick, etc., from mouser.
Thank you.