That's one nice amplifier!
Congrats, Bas.
Some multi-pin "aviation" connector wired to the box of 2mm banana sockets maybe?
Congrats, Bas.
Some multi-pin "aviation" connector wired to the box of 2mm banana sockets maybe?
The fact that I butchered the mains transformer to fit like that. Was not a recipe for a nice looking internal build.
I wanted to also build this beautifully "inside" this time....since I used PCB's which should make that a lot easier to achieve. It was not te be.
Bias supply= red wires = twisted since it has ac. And taped to the aluminium top cover with copper tape. The same for the heater wiring = blue wires.
Essentially there is a copper earth bus running diagonally on the mains transformer (but not connected...it is "floating" on the turrets). So everything goes to that (except rca input ground).
First of all from the ground "leg" of my rectifier/psu board in the middle. Then the transformer itself through from the bolt and therefore also the top plate. Then the internal screen of the transformer. The negative leg of the boards also connect to this earth bus. As I don't have rectifiers on each channel I have to be careful and connect - to earth and + to the positive part of the input. And last but not least the two 100ohm resistors from each leg of the heater supply.
Since I have a ground bus that is connected to the board...I have the connector ground for the bias xlr also connected only to the ground bus.
The output transformer just connects to the relevant connector and is not grounded anywhere. The big black heatsink is for future use.
Also the choke/resistor is bypassed with a wire. Because I want the 21st century Maida reg...and anything after that is really superfluous. But I'll probably put a big value resistor in there to get my temporary rectifier and psu board with lower voltage...so that comparison to the reg will be a more equal test.
I wanted to also build this beautifully "inside" this time....since I used PCB's which should make that a lot easier to achieve. It was not te be.
Bias supply= red wires = twisted since it has ac. And taped to the aluminium top cover with copper tape. The same for the heater wiring = blue wires.
Essentially there is a copper earth bus running diagonally on the mains transformer (but not connected...it is "floating" on the turrets). So everything goes to that (except rca input ground).
First of all from the ground "leg" of my rectifier/psu board in the middle. Then the transformer itself through from the bolt and therefore also the top plate. Then the internal screen of the transformer. The negative leg of the boards also connect to this earth bus. As I don't have rectifiers on each channel I have to be careful and connect - to earth and + to the positive part of the input. And last but not least the two 100ohm resistors from each leg of the heater supply.
Since I have a ground bus that is connected to the board...I have the connector ground for the bias xlr also connected only to the ground bus.
The output transformer just connects to the relevant connector and is not grounded anywhere. The big black heatsink is for future use.
Also the choke/resistor is bypassed with a wire. Because I want the 21st century Maida reg...and anything after that is really superfluous. But I'll probably put a big value resistor in there to get my temporary rectifier and psu board with lower voltage...so that comparison to the reg will be a more equal test.
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Hi Gerrit. Because of your question I went and checked. I thought the sticky side was conductive as well. But the adhesive is not conductive. I can't remember where I bought it. I can send you some if you like?
Did a search and both conductive and non-conductive adhesive types are sold at places like digikey and rs.
Did a search and both conductive and non-conductive adhesive types are sold at places like digikey and rs.
It's sold literally everywhere - eBay, Amazon, AliExpress, component distributors, guitar stores (it is widely used for shielding the electric guitar internals), etc.
Hi Bas,
Love your build.
Are these the item number for the
output transformers you bought?
VT-PP555
Thanks
Lee
Nah. Good output transformers come in all sizes and shapes.
Some alternatives:
TTG-EL84PP - Transformator głośnikowy [8kOhm] 2xEL84 PP Push-pull - Sklep Toroidy.pl
Gegentaktubertrager ATR 30 fur EL 84 | TBT Trafobau
Look for a power transformer with 250VAC/250mA secondary, 50VAC/20mA and 6,3V/5A.
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