The Ham Nation Pine Board Project

Discussion in 'Amateur Radio News' started by K9EID, Mar 8, 2017.

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  1. K7MD

    K7MD Premium Subscriber QRZ Page

    As I recall, Bob noted the lack of PS Bleeder resistor in the most recent video. He noted that as the total circuit load has not yet been determined, the precise value of the bleeder resistor is not yet determined either... He said it would be specified in the future.
  2. N4ACB

    N4ACB Ham Member QRZ Page

    A temporary bleeder resistor could be added until the final connections are made.
    Those charged caps could be a nasty surprise to all of us informed types the next day when we forget....

    KM1H likes this.
  3. K7MD

    K7MD Premium Subscriber QRZ Page

    I agree Mike. I was actually surprised he didn't just drop one in there temporarily.
    KM1H likes this.
  4. VE3LYX

    VE3LYX Ham Member QRZ Page

    Just finished my PSU and added 100 ohms per volt bleeder. Also keeps key up PSU voltage in reason. I can hardly wait for the TX build.
  5. KE4OH

    KE4OH Ham Member QRZ Page

    Joe, we would flame you, but flames are too dangerous. :)
  6. KE0EFX

    KE0EFX Ham Member QRZ Page

    Any photos of your work, Don? I just ordered some parts and will gradually catch up with you and the videos.
  7. VE3LYX

    VE3LYX Ham Member QRZ Page

    I am having trouble stopping!
    N0BML likes this.
  8. KE0EFX

    KE0EFX Ham Member QRZ Page

    I'm sorta confused. Heil's power supply has 1 transformer and 1 tube. Yours has 2 of each, will you explain?
  9. KF5FEI

    KF5FEI Ham Member QRZ Page

    I think he's working on the mic pre-amp. Note the solid-state bridge rectifier.
  10. VE3LYX

    VE3LYX Ham Member QRZ Page

    I used a bridge rectifier because I happened to have one. I built the PSU my way. Not that it is better in any way. It just reflects what is in my junk box. A low value 5 watt resistor stands in for what would be normally a choke. The caps are 20uf 450volt. The bleeder resistor is a little hi in value but in the ball park and much better then none. The second transformer is really a audio transformer but only the secondary is used (as the audio choke. because that is what I have in stock. ) The bare wire is Ground bus for those who like to worry. The second tube is there because there will be one. The mod section it says is driven by a audio pre amp or speech amp. 12ax7 s are often used there so I mounted it in right now. I still have to mount the crystal socket and Pi network . I left room for a pair of 12BH7 s for a quad four PA if it works well. (GG of course!)
    Last edited: Mar 14, 2017
    AF6LJ likes this.

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