PCB ORDER
Hello,
Going ahead, I am placing an order for 30 boards (option 3), with a price tag of USD 9 per PCB.
Specs of PCB 2.4 mm thick FR-4, double sided, green mask on both side, ENIG, white silk on top.
PCB manufacturing and delivery to me is expected in 18-20 days. Meanwhile I will send PM to get details of names, addresses, postal code and paypal to the subscribers. Once PCB are delivered, I will send out a paypal invoice, against which you can make payment. It will be shipped within 2 working days after payment is made.
please let me know any more requirements by tomorrow and also inform me of any cancellations so that i can adjust qty.
the current list is as follows
daniel goh 8 boards
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
total 28 nos.
regards
Prasi
Hello,
Going ahead, I am placing an order for 30 boards (option 3), with a price tag of USD 9 per PCB.
Specs of PCB 2.4 mm thick FR-4, double sided, green mask on both side, ENIG, white silk on top.
PCB manufacturing and delivery to me is expected in 18-20 days. Meanwhile I will send PM to get details of names, addresses, postal code and paypal to the subscribers. Once PCB are delivered, I will send out a paypal invoice, against which you can make payment. It will be shipped within 2 working days after payment is made.
please let me know any more requirements by tomorrow and also inform me of any cancellations so that i can adjust qty.
the current list is as follows
daniel goh 8 boards
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
total 28 nos.
regards
Prasi
Hello Prasi,
You can add 2 boards for me, I may rebuilt my amplifier with the thicker PCB and 500 V capacitors
Therefor you will have the 30 boards
the current list is as follows
daniel goh 8 boards
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
bandol83 2 boards
total 30 nos.
Best regards,
Marc
You can add 2 boards for me, I may rebuilt my amplifier with the thicker PCB and 500 V capacitors
Therefor you will have the 30 boards
the current list is as follows
daniel goh 8 boards
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
bandol83 2 boards
total 30 nos.
Best regards,
Marc
Improved version EL34 Baby Huey rev 2.1
Hello,
Since I have learned a lot with this small but very good amplifier since one year, I have made some minor modifications to simplify the assembly of this PCB :
1. I indicated the GND side on the input, feedback and bias connectors,
2. I removed the not very useful on board potentiometer for volume and replaced it with a 47k resistor
3. I increased a little the space between the bias and driver filter capacitors C10 and C11
4. I optimized the location and/or size of some name on the serigraphy
These modifications didn't change the functionality of the amplifier, but will make it easier to built
You can see a picture of the new PCB. The main modification (removing the pot) does not mean that you cannot use a pot on the input, but it will be connected by wire from the front panel.
Best regards,
Marc
Hello,
Since I have learned a lot with this small but very good amplifier since one year, I have made some minor modifications to simplify the assembly of this PCB :
1. I indicated the GND side on the input, feedback and bias connectors,
2. I removed the not very useful on board potentiometer for volume and replaced it with a 47k resistor
3. I increased a little the space between the bias and driver filter capacitors C10 and C11
4. I optimized the location and/or size of some name on the serigraphy
These modifications didn't change the functionality of the amplifier, but will make it easier to built
You can see a picture of the new PCB. The main modification (removing the pot) does not mean that you cannot use a pot on the input, but it will be connected by wire from the front panel.
Best regards,
Marc
Attachments
Hi Marc,
In case that, you have done some fixes on layout, if it's not trouble for you and before boards are produced, to place properly R41 & R42 to the corresponding tube? As we know R41 drives V3 tube and should drive the V2..just for the sake of the physical placement to not confuse which trimmer should be turn.
Another question I have, I read most of the thread especially for BH EL34. did you try with AC tube heaters? Any hum, noise? I'm asking you as, I see from your posts that, you purchase Toroidy transformers and they have 6.3V 7A out.
Many thanks,
bekim
In case that, you have done some fixes on layout, if it's not trouble for you and before boards are produced, to place properly R41 & R42 to the corresponding tube? As we know R41 drives V3 tube and should drive the V2..just for the sake of the physical placement to not confuse which trimmer should be turn.
Another question I have, I read most of the thread especially for BH EL34. did you try with AC tube heaters? Any hum, noise? I'm asking you as, I see from your posts that, you purchase Toroidy transformers and they have 6.3V 7A out.
Many thanks,
bekim
Hi Prasi,
If the new version Rev. 2.1 is produced in this GB
I'll take 2 boards.
Regards
TS
I'll take 2 boards....
daniel goh 8 boards
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
bandol83 2 boards
jims 2 boards
Lutto 4 boards
skippyboy 2 boards
mituisho 2 boards
meanie 2 boards
total 42 nos.
daniel goh 8 boards
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
bandol83 2 boards
jims 2 boards
Lutto 4 boards
skippyboy 2 boards
mituisho 2 boards
meanie 2 boards
total 42 nos.
daniel goh 8 boards
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
bandol83 2 boards
jims 2 boards
Lutto 4 boards
skippyboy 2 boards
mituisho 2 boards
TS Lo 2 boards
meanie 2 boards
total 44 nos.
RKH 2 boards
Dr.strangelove3 2 boards
mravinsky 2 boards
overtheairbroadcast 2 boards
jcastellano 2 boards
hallcon83 4 boards
davej 4 boards
mctavish 2 boards
bandol83 2 boards
jims 2 boards
Lutto 4 boards
skippyboy 2 boards
mituisho 2 boards
TS Lo 2 boards
meanie 2 boards
total 44 nos.
Hi Bekim,
Thanks for the suggestion, however, not only it is no more a minor change and it may create errors therefor a test batch should be made before production of 50 boards, but also the fact that the trimmer and the test point are not on the same side is not so bad because it is easier to have one hand on each side of this very compact amplifier to avoid to burn your fingers on the hot tubes
Regarding your second question about heaters, I have never used 6.3 V AC in this amplifier. At the beginning I have used a 10 A switching power supply from the main and after I have used two small Chinese 7 A DC/DC converter from the 9 V AC of my custom 141 VA transformer but the 25 A bridge rectifier be came quite hot ( two volt and nearly 7 A = 14 w loss in the bridge !) and after that the transformer was a little too small for this amplifier... Finally I am using the Toroidy and I put the two 6.3 V 7 A in serial to get about 15 V DC to drive the new 20 A DC/DC converter and since the current in the rectifier is much lower, about 3 A, I dissipate only 6 W in the bridge witch does not need a heatsink even if there is one on the picture
Best regards,
Marc
Thanks for the suggestion, however, not only it is no more a minor change and it may create errors therefor a test batch should be made before production of 50 boards, but also the fact that the trimmer and the test point are not on the same side is not so bad because it is easier to have one hand on each side of this very compact amplifier to avoid to burn your fingers on the hot tubes
Regarding your second question about heaters, I have never used 6.3 V AC in this amplifier. At the beginning I have used a 10 A switching power supply from the main and after I have used two small Chinese 7 A DC/DC converter from the 9 V AC of my custom 141 VA transformer but the 25 A bridge rectifier be came quite hot ( two volt and nearly 7 A = 14 w loss in the bridge !) and after that the transformer was a little too small for this amplifier... Finally I am using the Toroidy and I put the two 6.3 V 7 A in serial to get about 15 V DC to drive the new 20 A DC/DC converter and since the current in the rectifier is much lower, about 3 A, I dissipate only 6 W in the bridge witch does not need a heatsink even if there is one on the picture
Best regards,
Marc
