danfrank
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Hi All,
Time for another build thread from me. This time it's a Hiwatt DR201 build, the six EL34 version. Again, it's not gonna be an exact replica but the circuit will remain true to the DR201. So, here goes...
Above is the main circuit board. No turrets! Guess how long it took me to put it together?!? Not as long as if I used turrets on the board. LOL! Most resistors are 1W carbon film with a few 1/2 watters also. All capacitors are polyester film & foil, except for one.
Above is the power supply board and power transformers... There are 2 PTs, one for HV & bias, the second one for the tube filaments. This build, like my others, use parts that I have collected throughout the years so it will not be a total exact replica but will have the same electronic circuit as the original.
There are two HV supplies stacked on top of each other to get the required B+ voltage. Bias supply uses a full wave bridge rectifier so the amp will be very quiet when operating. For grounding, I am using a 12ga piece of solid copper wire attached to the chassis at one point, in the center.
Above is the bias and preamp power supply board, on the other end of the chassis. With six EL34 output tubes, getting all six to match up current-wise is not as easy as a 50 watt amp with 2 power tubes. I am using two 10 turn pots to adjust bias in each set of 3 EL34s in the push pull output circuit. All HV wiring is to the left at the back of the amp while the yellow bias wiring is to the right in the picture.
Time for another build thread from me. This time it's a Hiwatt DR201 build, the six EL34 version. Again, it's not gonna be an exact replica but the circuit will remain true to the DR201. So, here goes...

Above is the main circuit board. No turrets! Guess how long it took me to put it together?!? Not as long as if I used turrets on the board. LOL! Most resistors are 1W carbon film with a few 1/2 watters also. All capacitors are polyester film & foil, except for one.

Above is the power supply board and power transformers... There are 2 PTs, one for HV & bias, the second one for the tube filaments. This build, like my others, use parts that I have collected throughout the years so it will not be a total exact replica but will have the same electronic circuit as the original.
There are two HV supplies stacked on top of each other to get the required B+ voltage. Bias supply uses a full wave bridge rectifier so the amp will be very quiet when operating. For grounding, I am using a 12ga piece of solid copper wire attached to the chassis at one point, in the center.

Above is the bias and preamp power supply board, on the other end of the chassis. With six EL34 output tubes, getting all six to match up current-wise is not as easy as a 50 watt amp with 2 power tubes. I am using two 10 turn pots to adjust bias in each set of 3 EL34s in the push pull output circuit. All HV wiring is to the left at the back of the amp while the yellow bias wiring is to the right in the picture.