Thanks! I took some nice NOS parts from my parts bin
That blue ones are Philips Polypropylene Film Foil Capacitor 100pF 630V 1% (not polystyrene) Also used some black Wima PPS foil caps on 100nF
I'll attach my position number list that I have made for convenience. Might come in handy for future builders
Attachments
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Important Update:
Hello everyone.
The preamp is ready, and I am willing to move on with the next GB of V4H PCBs as well. But there is some kind of a problem regarding shipping. It is not fully stopped, but got complicated. Please read on...
I ship the packets to abroad primarily using the Air Parcel and the cheaper Registered Post services provided by IndiaPost. Now, due to the pandemic both services are now suspended and will probably remain suspended for another month. The only service that is available is EMS Speed Post which although is operational with some delays, is also more expensive than the previous two services. You can see a full list of the charges in the "Tariff" tab of the following link. In the page find your country and divide the shown charge in the first column with 75 to get the charge in US dollars. For some countries the charges are reasonable, while for a few countries it's prohibitively high.
IndiaPost EMS SpeedPost
Note that inland shipping is unaffected, although takes double the time as before.
.....................
Under these circumstances, I am not fully sure what to do next. I can definitely start the group buys and boards will be ready accordingly as the PCB fab here is fully operational. But if cheaper shipping method is desired, then the willing member(s) might have to wait for a longer time than usual, i.e. until the services resume. Of course the reserved boards will be with me safe and sound and will be shipped at the first scope - I already have a couple packets with V4 and V4H boards stuck with me from a couple orders from April to be shipped using registered post as requested by the buyers.
As I normally accept payment for shipping charges for international packets after I have the PCB batch from the fab in usually 25-30 days of ordering the batch, this means if I order the batch by July end, shipping will not start until August end, by which time the shipping conditions are supposed to improve compared to now, hopefully.
Feel free to post your thoughts.
Thanks
Hello everyone.
The preamp is ready, and I am willing to move on with the next GB of V4H PCBs as well. But there is some kind of a problem regarding shipping. It is not fully stopped, but got complicated. Please read on...
I ship the packets to abroad primarily using the Air Parcel and the cheaper Registered Post services provided by IndiaPost. Now, due to the pandemic both services are now suspended and will probably remain suspended for another month. The only service that is available is EMS Speed Post which although is operational with some delays, is also more expensive than the previous two services. You can see a full list of the charges in the "Tariff" tab of the following link. In the page find your country and divide the shown charge in the first column with 75 to get the charge in US dollars. For some countries the charges are reasonable, while for a few countries it's prohibitively high.
IndiaPost EMS SpeedPost
Note that inland shipping is unaffected, although takes double the time as before.
.....................
Under these circumstances, I am not fully sure what to do next. I can definitely start the group buys and boards will be ready accordingly as the PCB fab here is fully operational. But if cheaper shipping method is desired, then the willing member(s) might have to wait for a longer time than usual, i.e. until the services resume. Of course the reserved boards will be with me safe and sound and will be shipped at the first scope - I already have a couple packets with V4 and V4H boards stuck with me from a couple orders from April to be shipped using registered post as requested by the buyers.
As I normally accept payment for shipping charges for international packets after I have the PCB batch from the fab in usually 25-30 days of ordering the batch, this means if I order the batch by July end, shipping will not start until August end, by which time the shipping conditions are supposed to improve compared to now, hopefully.
Feel free to post your thoughts.
Thanks
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Hi Shaan,
Fantastic news that your preamp is ready!
I think you should move forward with the GB’s as normal. When you have the boards in hand and are ready to ship, at that point, if services are still suspended members can choose EMS or just wait. In the meantime the parts can be gathered and ready for building when the boards do arrive.
Fantastic news that your preamp is ready!
I think you should move forward with the GB’s as normal. When you have the boards in hand and are ready to ship, at that point, if services are still suspended members can choose EMS or just wait. In the meantime the parts can be gathered and ready for building when the boards do arrive.
As far as I'm concerned, shipment to France via EMS seems about 10% more expensive than your previous way, which is acceptable .....
What is not documented is the unusual time parcels stay in 'transit' in the various airports these days ....
JM
GB update:
Greg1017 - 2 PCBs + MOSFETS - PM SENT
Torvbakkane - 6 PCBS - PAID
satmmc86 - 2 MODULES - PM SENT
Faizal Mansar Alam - 2 MODULES - PM SENT
J.M.K - 4 PCBs - PAID
prairieboy - 2 PCBs - PAID
Pistollero- 2PCB + Mosfets - PAID
RobSoet 4pcb + Mosfets - PM SENT
Rick G - 4 PCBs - PAID
Remaining members are requested to respond to the PMs ASAP.
Thanks.
Greg1017 - 2 PCBs + MOSFETS - PM SENT
Torvbakkane - 6 PCBS - PAID
satmmc86 - 2 MODULES - PM SENT
Faizal Mansar Alam - 2 MODULES - PM SENT
J.M.K - 4 PCBs - PAID
prairieboy - 2 PCBs - PAID
Pistollero- 2PCB + Mosfets - PAID
RobSoet 4pcb + Mosfets - PM SENT
Rick G - 4 PCBs - PAID
Remaining members are requested to respond to the PMs ASAP.
Thanks.
It's my first amp build . Soft start and speaker protection both SSR are tested and working , going on with the mosfet fever i've made a four LT4320 bridges power supply . I'm getting 52v from a 35v toroid with 600R each rail - 65mv ripple pp made directly with the ground clip , looks very clean and quiet.
The question is . Speaker and power supply ground are going on the first 2 caps ? power supply wires have to be twisted , 10CM ( i have the white and grey 5mm flat wire seen on power supply but i can,t twist it)
It's not a CRC only a capacitor bank 6 X10.000 uf.
The question is . Speaker and power supply ground are going on the first 2 caps ? power supply wires have to be twisted , 10CM ( i have the white and grey 5mm flat wire seen on power supply but i can,t twist it)
It's not a CRC only a capacitor bank 6 X10.000 uf.
Hi Abanico.
That's a mighty build!
Here is a basic short circuit protection for the MOSFETs that will be implemented in the next revision of PCBs, shown in first attachment. You can install it right between the gate and source pins (pin 1 and pin 2) of each mosfet. Four networks needed per channel. You can easily make them the way shown in the second attachment. The diodes can stand vertically or lie down horizontally as per your convenience.
For Q11 and Q13, anode of 4148 (marked "A") goes to gate (pin1), and anode of zener (marked "B") goes to source (pin2). For Q12 and Q14, anode of 4148 goes to source (pin2), and anode of zener goes to gate (pin1). Cathodes of the two diodes are joined together in each network. Total diodes needed - 1N4148 x8 and 10V zener x8 for two channels. Typically half the number of diodes are used, but this way we bypass the gate resistors and have the protection right at individual mosfet gates.
It is not essential for normal operation of the amp but will save the mosfets in case of a short at the output happens.
Bests.
That's a mighty build!
Here is a basic short circuit protection for the MOSFETs that will be implemented in the next revision of PCBs, shown in first attachment. You can install it right between the gate and source pins (pin 1 and pin 2) of each mosfet. Four networks needed per channel. You can easily make them the way shown in the second attachment. The diodes can stand vertically or lie down horizontally as per your convenience.
For Q11 and Q13, anode of 4148 (marked "A") goes to gate (pin1), and anode of zener (marked "B") goes to source (pin2). For Q12 and Q14, anode of 4148 goes to source (pin2), and anode of zener goes to gate (pin1). Cathodes of the two diodes are joined together in each network. Total diodes needed - 1N4148 x8 and 10V zener x8 for two channels. Typically half the number of diodes are used, but this way we bypass the gate resistors and have the protection right at individual mosfet gates.
It is not essential for normal operation of the amp but will save the mosfets in case of a short at the output happens.
Bests.
Attachments
GB update:
Greg1017 - 2 PCBs + MOSFETS - INVOICE SENT
Torvbakkane - 6 PCBs - PAID
satmmc86 - 2 MODULES - PM SENT
Faizal Mansar Alam - 2 MODULES - PM SENT
J.M.K - 4 PCBs - PAID
prairieboy - 2 PCBs - PAID
Pistollero - 2 PCBs + MOSFETS - PAID
RobSoet - 4 PCBs + MOSFETS - PAID
Rick G - 4 PCBs - PAID
blek stena - 2 PCBs - PAID
Greg1017 - 2 PCBs + MOSFETS - INVOICE SENT
Torvbakkane - 6 PCBs - PAID
satmmc86 - 2 MODULES - PM SENT
Faizal Mansar Alam - 2 MODULES - PM SENT
J.M.K - 4 PCBs - PAID
prairieboy - 2 PCBs - PAID
Pistollero - 2 PCBs + MOSFETS - PAID
RobSoet - 4 PCBs + MOSFETS - PAID
Rick G - 4 PCBs - PAID
blek stena - 2 PCBs - PAID
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Thanks Shaan for the new added protection .
I've made something for the leds that is good for thick panels . They are quite impossible to dim and always offending in the dark . 4mm metacrylate screw, cut the head ,thread tap the panel ,sand, polish the plastic end .Place 2 hexnuts , stick the second one with adhesive and cut the plastic at the end . Now is easy just buy a 5mm led panel holder and attach it to the nuts with two cuts of heatshink ,diameters are similar.Now the led is seen threw the plastic and nothing stands out aluminium . If it's not enough on two of them i've placed just a piece of paper between to see just an illuminated colour.
PS.idea coming from the 70's disco.
I've made something for the leds that is good for thick panels . They are quite impossible to dim and always offending in the dark . 4mm metacrylate screw, cut the head ,thread tap the panel ,sand, polish the plastic end .Place 2 hexnuts , stick the second one with adhesive and cut the plastic at the end . Now is easy just buy a 5mm led panel holder and attach it to the nuts with two cuts of heatshink ,diameters are similar.Now the led is seen threw the plastic and nothing stands out aluminium . If it's not enough on two of them i've placed just a piece of paper between to see just an illuminated colour.
PS.idea coming from the 70's disco.