Search:

Type: Posts; User: J M Fahey; Keyword(s):

Page 1 of 18 1 2 3 4

Search: Search took 0.06 seconds; generated 11 minute(s) ago.

  1. Replies
    29
    Views
    591

    In principle save a lot by using light 1/2"...

    In principle save a lot by using light 1/2" plywood, the thinnest one which can still be nailed or screwed without splitting and a single 12" Guitar Type Neo speaker.
    Forget PA speakers, you NEED...
  2. Replies
    57
    Views
    925

    My take since forever is that "RMS power" should...

    My take since forever is that "RMS power" should have been written as :"Power calculated using measured RMS Voltage"
    I guess this is the implicit assumption used by everybody for decades now ......
  3. Replies
    2
    Views
    99

    Just curious (very) about your: a does not...

    Just curious (very) about your:

    a does not explain that.
    Care to elaborate?

    Maybe post a PCB picture and say: "I didnīt have continuity between here and here"
  4. Replies
    57
    Views
    925

    Well, it should look similar to a full wave...

    Well, it should look similar to a full wave rectified one, since both negative and positive halves become positive when squared.
  5. Replies
    13
    Views
    217

    Current trend everywhere, not only at fender, is...

    Current trend everywhere, not only at fender, is to use an "80% of a full amp" Ice Power module and just design a preamp.
    Such modules offer dual supplies, +/-28V or thereabouts to supply preamps;...
  6. Replies
    17
    Views
    284

    What chuck h said, period. To please bedroom...

    What chuck h said, period.
    To please bedroom wankers playing alone (and this is the key word) typical trick to get a "huge" :confused: sound is to apply a "Smiley" curve, meaning boosy highs and...
  7. "First fix DC, then Audio" Meaning: first ...

    "First fix DC, then Audio"

    Meaning: first measure and post voltage on all IC pins.
    Then if normal start checking signal along the path from input to output to see where it gets lost.
  8. GK typical tone controls are cut-boost active...

    GK typical tone controls are cut-boost active feedback type, not passive like F/M/V types, so the ground open trick does not work here.

    Thgere might be an open track though, just not necessarily...
  9. Thread: Tube tester

    by J M Fahey
    Replies
    13
    Views
    256

    I would send it back and recover money, period....

    I would send it back and recover money, period.
    Itīs a scam so nobody knows what else could be broken.
    It could NEVER have worked that way and although wires can break in transit, theu donīt attach...
  10. Replies
    15
    Views
    164

    Actual **bulbs**? :confused: Not LEDs? And...

    Actual **bulbs**? :confused:
    Not LEDs?

    And why mention a schematic and not post it here?

    Yet we are supposed to answer something useful?

    It beats me.
  11. Replies
    11
    Views
    543

    I guess "not using a Variac" does not imply...

    I guess "not using a Variac" does not imply "using a lightbulb limiter instead"
    Just checking.
  12. Replies
    6
    Views
    192

    Please be careful 5V rectifier windings are not...

    Please be careful
    5V rectifier windings are not same as "a standard 6V filament winding, just putting out 5V" by any means.
    Filament windings expect to live grounded or worst case elevated a few...
  13. Replies
    57
    Views
    925

    Thanks. Luckily it lasted only 4 hours and...

    Thanks.
    Luckily it lasted only 4 hours and apparently followed the exact same path as the US one: branches trying to cover for main line sections and dropping themselves.
  14. Irt definitely might, so itīs worth checking. ...

    Irt definitely might, so itīs worth checking.

    That said, I guess today_not_so_popular 16 ohm choice by Marshall (an d some Laney and Vox amps, all "British" *may* be to push users to get some 16...
  15. Replies
    57
    Views
    925

    GW is a confirmed trick man, just like that. Or...

    GW is a confirmed trick man, just like that.
    Or uses typical Politician tricks to catch audience... same thing.

    His video is crap useless, all it tells you is that amp is "workung" ... which you...
  16. Replies
    40
    Views
    797

    Above ideas are excelent but the easiest to...

    Above ideas are excelent but the easiest to UN-mod back to normal (do you think he wonīt change his mind at random?) and to boot *effective* , you get as many dB down as you wish, no 3 or 6 dB by...
  17. Replies
    19
    Views
    4,235

    Yes, search how Hi Fi amplifier "balance control"...

    Yes, search how Hi Fi amplifier "balance control" is made, or active bass pickup blending.

    Basically:
    1) you join grids
    2) plates are separate, each one goes to its own output volume control....
  18. Replies
    3
    Views
    166

    Agree and add: maybe you can get a "normal" pot...

    Agree and add: maybe you can get a "normal" pot with proper size and shaft, and instead of plain wires, you use brass wire to replace the long legs, so replacement keeps reasonably holding the PCB....
  19. Replies
    46
    Views
    880

    Vox really LOVED inverting input Op Amps, itīs...

    Vox really LOVED inverting input Op Amps, itīs all the SuprTwin uses: input preamp - reverb drive - reverb recovery - Baxandall tone control
    ...
  20. What current does your pedal need? Absolute...

    What current does your pedal need?
    Absolute worst case, measure when you get it, being analog power consumption "should" be reasonable .
    Battery indicators use power for themselves, so one old Boss...
  21. Replies
    14
    Views
    1,284

    In any case, 14mV offset is not enough to trigger...

    In any case, 14mV offset is not enough to trigger any speaker protection.
  22. Replies
    36
    Views
    668

    Sorry MrC but I asked you to make all corrections...

    Sorry MrC but I asked you to make all corrections RED for a reason. :)

    I am jumping back and forth comparing values and half the time I lose track (since we OCD people focus on *one* issue at a...
  23. Replies
    19
    Views
    469

    Cool. So you were straight missing your first...

    Cool.
    So you were straight missing your first power filter.
    That explains both the massive (unfiltered) hum and the 30% lower "DC Voltage" ... although it was not real DC but unfiltered full wave...
  24. Replies
    17
    Views
    275

    Simplest "practical" charger is a power supply...

    Simplest "practical" charger is a power supply with maximum desired voltage , say 16V which is 100% charge, and with a limiting resistor so when charging a real flat battery (11V or so) current is...
  25. Replies
    11
    Views
    324

    https://www.youtube.com/watch?v=uzb6zDFg3WQ

    https://www.youtube.com/watch?v=uzb6zDFg3WQ
  26. Replies
    2
    Views
    317

    Sorry but not compatible. This is the 8100 head,...

    Sorry but not compatible.
    This is the 8100 head, single 100W RMS into 4 ohm, rails about +/- 40V
    Besides, it does not have a high voltage winding, it uses a separate sutotranformer .

    }VS 8240...
  27. Replies
    17
    Views
    275

    1) get two new batteries 2) Sealed Lead Acid...

    1) get two new batteries

    2) Sealed Lead Acid batteries need an SLA charger,period.
    They are as complicated as NiCads, Lithium, NiMh, etc. , just with their own set of rules.

    Repeat with me:...
  28. Replies
    19
    Views
    469

    Like G1 said, your meter can not measure AC if...

    Like G1 said, your meter can not measure AC if mixed with DC so you can not measure ripple (you still can measure mains and transformer windings though)
    So "800VAC" means nothing in this case.
    ...
Results 1 to 28 of 489
Page 1 of 18 1 2 3 4