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Re: [Altair Computer Club] Re: Hardware Question for an Altair 8800

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  • Douglas Allen
    Thanks Bob, * This is an original Altair, before the a/b designations * I did press the Stop and Reset in various orders, including Stop, then Reset, Then let
    Message 1 of 26 , May 31 6:40 AM
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      Thanks Bob,
      * This is an original Altair, before the a/b designations
      * I did press the Stop and Reset in various orders, including Stop, then Reset, Then let go of Reset, then let go of Stop etc., no change
      * I have checked the clock signal on the bus. It's clicking along at somewhere between 2 and 2.22 Mhz, so at least that is working. Found three on board regulators. As you say, two of them were zener diodes: one for the -5 volts, and one for the +12 volts. The third on board regulator is a 7822 for the 5 volts. All tested perfectly.
      * I do have a 4 trace 400 Mhz scope, but don't know which clock signal traces to check phases on. Since I am still new at all this, don't know where there should be an inverted signal for instance. Any rough ideas?
      * I made the assumption that this old a computer would be tough to find equivalent ICs for. Do they still make the same ICs today, that could just be replaced? Or were you thinking scavenging some older hardware for these swaps. If it came time to swapping ICs, I might obtain and entire CPU board. But would like to be sure it is not the display board first.

      Thanks again for your help. I'll need it but this has been a fun project so far.


      ----- Original Message -----
      From: H.E. Robert, [Just Bob!]
      To: altaircomputerclub@yahoogroups.com
      Sent: 5/30/2004 1:06:37 PM
      Subject: Re: [Altair Computer Club] Re: Hardware Question for an Altair 8800


      Hi Doug,

      Again, this was an "original" Altair, not a or b, right? So I think as
      Steve said, on these it's always best to raise the stop then reset, and
      release them in reverse order to insure the CPU is halted.

      Any lights flashing means there is some "brain activity" going on in the
      CPU and hitting the buss, however, the solid "on" data led's aren't
      sending their state to the front panel, and since the reset isn't
      operating correctly, it might be too soon to rule out the FP yet?

      You should see a different led pattern on D0-D7 with the molex connector
      attached, all on is correct for no connection, but with it connected,
      you should be able change the pattern via deposit/next.

      I would start by checking source voltages at several points on the
      boards, at the major chip locations, there are a couple of 12V Zeners on
      the orig cpu board, instead of the 7812, so you should have the raw 16v
      in and 12v coming out, if the voltages or good, then if you can Scope
      the clock signals and check the phases (old dual trace scope) would help
      here.

      If all checks out okay, then isolate a function, like the Data led's,
      and trace the logic, or if the chips are in sockets, do what I do, and
      swap with another known good chip, I don't have the orig Altair
      schematic here, but I thought there was an 8212 latch on the CPU BD that
      is in common with all the data lines, might be a good place to start?
      After that, it's very basic buffers, drivers, and inverter logic, the
      system description in the original manuals give a pretty good step by
      step of the logic and functions as to what should be hi, lo, or tri-stated.

      Good luck, and keep us posted!

      Just Bob!

      dougls12000 wrote:

      > OK, obtained a "new" power supply and installed it. True to form,
      > about 7.8 VAC this time. Now the "5 volt" bus pin 1 and 51 read 10
      > volts, which is the same voltage as my Imsai 8080, so believe the
      > power supply problem is fixed.
      >
      > Still have the same problem with lack of responsiveness and too many
      > lights.
      > Here is the behavior:
      > 1) With no board installed and power on:
      > D0 - D7 are lit
      > 2) CPU Board installed but 8 pin display not connected:
      > D0 - D7 and INTE LEDs are lit
      > 3) CPU Board installed and 8 pin display connected:
      > No change from scenario#2
      > 4) CPU Board and 16K static board Installed (both my 16K boards
      > reacted identically)
      > No change from Scenario#2
      > 5) Hit reset with scenario #4
      > A0 - A13 LEDs lit
      > A14 - Blinking very rapidly
      > A15 - Blinking about 8 times per second
      > D0 - D7 lit
      > Other testing:
      > Onboard regulators for the display board and CPU board all
      > around +5 volts
      >
      > Anyone have ideas on next steps? Does this appear like stictly a CPU
      > Board problem (versus a display board problem)? I have all the
      > manuals and schematics.
      >
      >
      > --- In altaircomputerclub@yahoogroups.com, "Steve" <alltare@y...>
      > wrote:
      > > Overkill on the Amps, but it should sure work. You could also
      > > substitute a variable bench power supply for the Altair's entire
      > +8V
      > > circuitry, for testing purposes.
      > >
      > > I use these 2 places a lot for parts:
      > > http://www.digikey.com/
      > > http://www.mouser.com/
      > >
      > > For cheap, weird, and surplus stuff, I use these:
      > > http://www.allcorp.com/
      > > http://www.goldmine-elec.com/
      > > http://www.fairradio.com/
      > > http://www.jameco.com/
      > > http://www.sciplus.com/
      > >
      > > If I must have a part "right now", and quality and price aren't as
      > > important as convenience, I use Radio Shack parts, too.
      > >
      > > Steve
      > > ===============================
      > >
      > > --- In altaircomputerclub@yahoogroups.com, "H.E. Robert, [Just
      > Bob!]"
      > > <robert@a...> wrote:
      > > > Doug, and distinguished list members....
      > > >
      > > > Here's a source I use for components, they aren't bargain
      > basement,
      > > but
      > > > they are a good source for "weird stuff"! The catalog page I've
      > > > included in the link, is for Stancor Transformers, and item
      > number
      > > > 928-2170 may do the trick, it's 16 volts center tapped @ 11 amps,
      > > that's
      > > > 8 volts @ 22 amps by my feeble mind, and costs $34
      > > >
      > > > > 928-2170 TGC175-16 B 175 16.0 V C.T. @ 11.00 A 8.0 V @ 22.00 A
      > > 3.750
      > > > > 3.130 2.880 2.500 2.500 0.380 0.250 33.99 31.69
      > > >
      > > > http://www.alliedelec.com/catalog/pf.asp?FN=631.pdf
      > > >
      > > > Anybody else have a good source for this kind of thing?
      > > >
      > > > Hope it helps!
      > > >
      > > > Just Bob!
      > > ...
      >
      >
      > Yahoo! Groups Sponsor
      > ADVERTISEMENT
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      >
      >
      >
      > ------------------------------------------------------------------------
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      >
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      >
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      >
      >


      [Non-text portions of this message have been removed]


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    • H.E. Robert, [Just Bob!]
      Hi Doug, The clock sounds okay, I don t remember them drifting much, might indicate a marginal capacitor in the circuit. As far as the clock source, it s
      Message 2 of 26 , May 31 4:15 PM
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        Hi Doug,
        The clock sounds okay, I don't remember them drifting much, might
        indicate a marginal capacitor in the circuit. As far as the clock
        source, it's describe in the theory of operation part of the system
        doc's, mine aren't handy, as I'm preparing to move, but I believe there
        were 2 phases something like phase 2 triggered on the trailing edge of
        phase 1, don't trust me on this one, check the doc's to be sure, I
        believe they were provided by the 8224 chip. As far as the chips go,
        most are still available out of the 7400 ttl series, some of the L and
        LS series are interchangeable, the tristate drivers 8T97 etc might be
        harder to find, the 8212 chips are getting tough, but some retailers are
        offering recycled chip-pulls, Jameco is one.
        Keep plugin' away!
        Just Bob!

        Douglas Allen wrote:

        > Thanks Bob,
        > * This is an original Altair, before the a/b designations
        > * I did press the Stop and Reset in various orders, including Stop,
        > then Reset, Then let go of Reset, then let go of Stop etc., no change
        > * I have checked the clock signal on the bus. It's clicking along at
        > somewhere between 2 and 2.22 Mhz, so at least that is working. Found
        > three on board regulators. As you say, two of them were zener diodes:
        > one for the -5 volts, and one for the +12 volts. The third on board
        > regulator is a 7822 for the 5 volts. All tested perfectly.
        > * I do have a 4 trace 400 Mhz scope, but don't know which clock signal
        > traces to check phases on. Since I am still new at all this, don't
        > know where there should be an inverted signal for instance. Any rough
        > ideas?
        > * I made the assumption that this old a computer would be tough to
        > find equivalent ICs for. Do they still make the same ICs today, that
        > could just be replaced? Or were you thinking scavenging some older
        > hardware for these swaps. If it came time to swapping ICs, I might
        > obtain and entire CPU board. But would like to be sure it is not the
        > display board first.
        >
        > Thanks again for your help. I'll need it but this has been a fun
        > project so far.
        >
        >
        > ----- Original Message -----
        > From: H.E. Robert, [Just Bob!]
        > To: altaircomputerclub@yahoogroups.com
        > Sent: 5/30/2004 1:06:37 PM
        > Subject: Re: [Altair Computer Club] Re: Hardware Question for an
        > Altair 8800
        >
        >
        > Hi Doug,
        >
        > Again, this was an "original" Altair, not a or b, right? So I think as
        > Steve said, on these it's always best to raise the stop then reset, and
        > release them in reverse order to insure the CPU is halted.
        >
        > Any lights flashing means there is some "brain activity" going on in the
        > CPU and hitting the buss, however, the solid "on" data led's aren't
        > sending their state to the front panel, and since the reset isn't
        > operating correctly, it might be too soon to rule out the FP yet?
        >
        > You should see a different led pattern on D0-D7 with the molex connector
        > attached, all on is correct for no connection, but with it connected,
        > you should be able change the pattern via deposit/next.
        >
        > I would start by checking source voltages at several points on the
        > boards, at the major chip locations, there are a couple of 12V Zeners on
        > the orig cpu board, instead of the 7812, so you should have the raw 16v
        > in and 12v coming out, if the voltages or good, then if you can Scope
        > the clock signals and check the phases (old dual trace scope) would help
        > here.
        >
        > If all checks out okay, then isolate a function, like the Data led's,
        > and trace the logic, or if the chips are in sockets, do what I do, and
        > swap with another known good chip, I don't have the orig Altair
        > schematic here, but I thought there was an 8212 latch on the CPU BD that
        > is in common with all the data lines, might be a good place to start?
        > After that, it's very basic buffers, drivers, and inverter logic, the
        > system description in the original manuals give a pretty good step by
        > step of the logic and functions as to what should be hi, lo, or
        > tri-stated.
        >
        > Good luck, and keep us posted!
        >
        > Just Bob!
        >
        > dougls12000 wrote:
        >
        > > OK, obtained a "new" power supply and installed it. True to form,
        > > about 7.8 VAC this time. Now the "5 volt" bus pin 1 and 51 read 10
        > > volts, which is the same voltage as my Imsai 8080, so believe the
        > > power supply problem is fixed.
        > >
        > > Still have the same problem with lack of responsiveness and too many
        > > lights.
        > > Here is the behavior:
        > > 1) With no board installed and power on:
        > > D0 - D7 are lit
        > > 2) CPU Board installed but 8 pin display not connected:
        > > D0 - D7 and INTE LEDs are lit
        > > 3) CPU Board installed and 8 pin display connected:
        > > No change from scenario#2
        > > 4) CPU Board and 16K static board Installed (both my 16K boards
        > > reacted identically)
        > > No change from Scenario#2
        > > 5) Hit reset with scenario #4
        > > A0 - A13 LEDs lit
        > > A14 - Blinking very rapidly
        > > A15 - Blinking about 8 times per second
        > > D0 - D7 lit
        > > Other testing:
        > > Onboard regulators for the display board and CPU board all
        > > around +5 volts
        > >
        > > Anyone have ideas on next steps? Does this appear like stictly a CPU
        > > Board problem (versus a display board problem)? I have all the
        > > manuals and schematics.
        > >
        > >
        > > --- In altaircomputerclub@yahoogroups.com, "Steve" <alltare@y...>
        > > wrote:
        > > > Overkill on the Amps, but it should sure work. You could also
        > > > substitute a variable bench power supply for the Altair's entire
        > > +8V
        > > > circuitry, for testing purposes.
        > > >
        > > > I use these 2 places a lot for parts:
        > > > http://www.digikey.com/
        > > > http://www.mouser.com/
        > > >
        > > > For cheap, weird, and surplus stuff, I use these:
        > > > http://www.allcorp.com/
        > > > http://www.goldmine-elec.com/
        > > > http://www.fairradio.com/
        > > > http://www.jameco.com/
        > > > http://www.sciplus.com/
        > > >
        > > > If I must have a part "right now", and quality and price aren't as
        > > > important as convenience, I use Radio Shack parts, too.
        > > >
        > > > Steve
        > > > ===============================
        > > >
        > > > --- In altaircomputerclub@yahoogroups.com, "H.E. Robert, [Just
        > > Bob!]"
        > > > <robert@a...> wrote:
        > > > > Doug, and distinguished list members....
        > > > >
        > > > > Here's a source I use for components, they aren't bargain
        > > basement,
        > > > but
        > > > > they are a good source for "weird stuff"! The catalog page I've
        > > > > included in the link, is for Stancor Transformers, and item
        > > number
        > > > > 928-2170 may do the trick, it's 16 volts center tapped @ 11 amps,
        > > > that's
        > > > > 8 volts @ 22 amps by my feeble mind, and costs $34
        > > > >
        > > > > > 928-2170 TGC175-16 B 175 16.0 V C.T. @ 11.00 A 8.0 V @ 22.00 A
        > > > 3.750
        > > > > > 3.130 2.880 2.500 2.500 0.380 0.250 33.99 31.69
        > > > >
        > > > > http://www.alliedelec.com/catalog/pf.asp?FN=631.pdf
        > > > >
        > > > > Anybody else have a good source for this kind of thing?
        > > > >
        > > > > Hope it helps!
        > > > >
        > > > > Just Bob!
        > > > ...
        > >
        > >
        > > Yahoo! Groups Sponsor
        > > ADVERTISEMENT
        > >
        > <http://rd.yahoo.com/SIG=129rmhg9e/M=295196.4901138.6071305.3001176/D=groups/S=1705566162:HM/EXP=1085965900/A=2128215/R=0/SIG=10se96mf6/*http://companion.yahoo.com>
        >
        > >
        > >
        > >
        > > ------------------------------------------------------------------------
        > > Yahoo! Groups Links
        > >
        > > * To visit your group on the web, go to:
        > > http://groups.yahoo.com/group/altaircomputerclub/
        > >
        > > * To unsubscribe from this group, send an email to:
        > > altaircomputerclub-unsubscribe@yahoogroups.com
        > >
        > <mailto:altaircomputerclub-unsubscribe@yahoogroups.com?subject=Unsubscribe>
        > >
        > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of
        > > Service <http://docs.yahoo.com/info/terms/>.
        > >
        > >
        >
        >
        > [Non-text portions of this message have been removed]
        >
        >
        > Yahoo! Groups Sponsor
        > ADVERTISEMENT
        >
        >
        >
        >
        >
        >
        > Yahoo! Groups Links
        >
        > To visit your group on the web, go to:
        > http://groups.yahoo.com/group/altaircomputerclub/
        >
        > To unsubscribe from this group, send an email to:
        > altaircomputerclub-unsubscribe@yahoogroups.com
        >
        > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
        >
        > [Non-text portions of this message have been removed]
        >
        >
        > Yahoo! Groups Sponsor
        > ADVERTISEMENT
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        >
        >
        >
        > ------------------------------------------------------------------------
        > Yahoo! Groups Links
        >
        > * To visit your group on the web, go to:
        > http://groups.yahoo.com/group/altaircomputerclub/
        >
        > * To unsubscribe from this group, send an email to:
        > altaircomputerclub-unsubscribe@yahoogroups.com
        > <mailto:altaircomputerclub-unsubscribe@yahoogroups.com?subject=Unsubscribe>
        >
        > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of
        > Service <http://docs.yahoo.com/info/terms/>.
        >
        >


        [Non-text portions of this message have been removed]
      • dougls12000
        OK, measured a great deal over the past week. What I need to know, is just whether my problem is in the CPU board or in the Display board, and what
        Message 3 of 26 , Jun 7, 2004
        • 0 Attachment
          OK, measured a great deal over the past week.
          What I need to know, is just whether my problem is in the CPU board
          or in the Display board, and what specifically seems to be going on?

          I have added an Excel spreadsheet file to the library, with each
          pin's high/low/or actual voltage status when I first turn the
          computer on, and then after resetting. When the voltage is 1 or 2
          volts, it means it has a frequency, with a certain number of clock
          cycles high, and others low, resulting in a lower than 5 volt signal.

          As you can see, upon resetting, the data-in lines are high all the
          time, and the data out and address lines are rapidly pulsing. I have
          tested all three clock pins (phase I, Phase 2 and the inverted phase
          2 clock signal on pin 49), and they are all fine. When I put the 2
          channel scope on the clock and on address 5, the address line stays
          on for 3 clock signals, and off for about 8. On address 15, it stays
          on for about 12, and off for 3. It appears all the address lines have
          their own frequency.

          Is there some feedback loop or some data-in generator that is stuck?
          If so, how could I find the source?

          And by the way, I have set this spreadsheet up as a neat trouble
          shooting tool for those who are trying to trace logic and board
          problems. Some hobbyists might be interested.


          --- In altaircomputerclub@yahoogroups.com, "H.E. Robert, [Just Bob!]"
          <robert@a...> wrote:
          > Hi Doug,
          > The clock sounds okay, I don't remember them drifting much, might
          > indicate a marginal capacitor in the circuit. As far as the clock
          > source, it's describe in the theory of operation part of the system
          > doc's, mine aren't handy, as I'm preparing to move, but I believe
          there
          > were 2 phases something like phase 2 triggered on the trailing edge
          of
          > phase 1, don't trust me on this one, check the doc's to be sure, I
          > believe they were provided by the 8224 chip. As far as the chips
          go,
          > most are still available out of the 7400 ttl series, some of the L
          and
          > LS series are interchangeable, the tristate drivers 8T97 etc might
          be
          > harder to find, the 8212 chips are getting tough, but some
          retailers are
          > offering recycled chip-pulls, Jameco is one.
          > Keep plugin' away!
          > Just Bob!
          >
          > Douglas Allen wrote:
          >
          > > Thanks Bob,
          > > * This is an original Altair, before the a/b designations
          > > * I did press the Stop and Reset in various orders, including
          Stop,
          > > then Reset, Then let go of Reset, then let go of Stop etc., no
          change
          > > * I have checked the clock signal on the bus. It's clicking along
          at
          > > somewhere between 2 and 2.22 Mhz, so at least that is working.
          Found
          > > three on board regulators. As you say, two of them were zener
          diodes:
          > > one for the -5 volts, and one for the +12 volts. The third on
          board
          > > regulator is a 7822 for the 5 volts. All tested perfectly.
          > > * I do have a 4 trace 400 Mhz scope, but don't know which clock
          signal
          > > traces to check phases on. Since I am still new at all this,
          don't
          > > know where there should be an inverted signal for instance. Any
          rough
          > > ideas?
          > > * I made the assumption that this old a computer would be tough
          to
          > > find equivalent ICs for. Do they still make the same ICs today,
          that
          > > could just be replaced? Or were you thinking scavenging some
          older
          > > hardware for these swaps. If it came time to swapping ICs, I
          might
          > > obtain and entire CPU board. But would like to be sure it is not
          the
          > > display board first.
          > >
          > > Thanks again for your help. I'll need it but this has been a fun
          > > project so far.
          > >
          > >
          > > ----- Original Message -----
          > > From: H.E. Robert, [Just Bob!]
          > > To: altaircomputerclub@yahoogroups.com
          > > Sent: 5/30/2004 1:06:37 PM
          > > Subject: Re: [Altair Computer Club] Re: Hardware Question for an
          > > Altair 8800
          > >
          > >
          > > Hi Doug,
          > >
          > > Again, this was an "original" Altair, not a or b, right? So I
          think as
          > > Steve said, on these it's always best to raise the stop then
          reset, and
          > > release them in reverse order to insure the CPU is halted.
          > >
          > > Any lights flashing means there is some "brain activity" going on
          in the
          > > CPU and hitting the buss, however, the solid "on" data led's
          aren't
          > > sending their state to the front panel, and since the reset isn't
          > > operating correctly, it might be too soon to rule out the FP yet?
          > >
          > > You should see a different led pattern on D0-D7 with the molex
          connector
          > > attached, all on is correct for no connection, but with it
          connected,
          > > you should be able change the pattern via deposit/next.
          > >
          > > I would start by checking source voltages at several points on the
          > > boards, at the major chip locations, there are a couple of 12V
          Zeners on
          > > the orig cpu board, instead of the 7812, so you should have the
          raw 16v
          > > in and 12v coming out, if the voltages or good, then if you can
          Scope
          > > the clock signals and check the phases (old dual trace scope)
          would help
          > > here.
          > >
          > > If all checks out okay, then isolate a function, like the Data
          led's,
          > > and trace the logic, or if the chips are in sockets, do what I
          do, and
          > > swap with another known good chip, I don't have the orig Altair
          > > schematic here, but I thought there was an 8212 latch on the CPU
          BD that
          > > is in common with all the data lines, might be a good place to
          start?
          > > After that, it's very basic buffers, drivers, and inverter logic,
          the
          > > system description in the original manuals give a pretty good
          step by
          > > step of the logic and functions as to what should be hi, lo, or
          > > tri-stated.
          > >
          > > Good luck, and keep us posted!
          > >
          > > Just Bob!
          > >
          > > dougls12000 wrote:
          > >
          > > > OK, obtained a "new" power supply and installed it. True to
          form,
          > > > about 7.8 VAC this time. Now the "5 volt" bus pin 1 and 51 read
          10
          > > > volts, which is the same voltage as my Imsai 8080, so believe
          the
          > > > power supply problem is fixed.
          > > >
          > > > Still have the same problem with lack of responsiveness and too
          many
          > > > lights.
          > > > Here is the behavior:
          > > > 1) With no board installed and power on:
          > > > D0 - D7 are lit
          > > > 2) CPU Board installed but 8 pin display not connected:
          > > > D0 - D7 and INTE LEDs are lit
          > > > 3) CPU Board installed and 8 pin display connected:
          > > > No change from scenario#2
          > > > 4) CPU Board and 16K static board Installed (both my 16K boards
          > > > reacted identically)
          > > > No change from Scenario#2
          > > > 5) Hit reset with scenario #4
          > > > A0 - A13 LEDs lit
          > > > A14 - Blinking very rapidly
          > > > A15 - Blinking about 8 times per second
          > > > D0 - D7 lit
          > > > Other testing:
          > > > Onboard regulators for the display board and CPU board all
          > > > around +5 volts
          > > >
          > > > Anyone have ideas on next steps? Does this appear like stictly
          a CPU
          > > > Board problem (versus a display board problem)? I have all the
          > > > manuals and schematics.
          > > >
          > > >
          > > > --- In altaircomputerclub@yahoogroups.com, "Steve"
          <alltare@y...>
          > > > wrote:
          > > > > Overkill on the Amps, but it should sure work. You could also
          > > > > substitute a variable bench power supply for the Altair's
          entire
          > > > +8V
          > > > > circuitry, for testing purposes.
          > > > >
          > > > > I use these 2 places a lot for parts:
          > > > > http://www.digikey.com/
          > > > > http://www.mouser.com/
          > > > >
          > > > > For cheap, weird, and surplus stuff, I use these:
          > > > > http://www.allcorp.com/
          > > > > http://www.goldmine-elec.com/
          > > > > http://www.fairradio.com/
          > > > > http://www.jameco.com/
          > > > > http://www.sciplus.com/
          > > > >
          > > > > If I must have a part "right now", and quality and price
          aren't as
          > > > > important as convenience, I use Radio Shack parts, too.
          > > > >
          > > > > Steve
          > > > > ===============================
          > > > >
          > > > > --- In altaircomputerclub@yahoogroups.com, "H.E. Robert, [Just
          > > > Bob!]"
          > > > > <robert@a...> wrote:
          > > > > > Doug, and distinguished list members....
          > > > > >
          > > > > > Here's a source I use for components, they aren't bargain
          > > > basement,
          > > > > but
          > > > > > they are a good source for "weird stuff"! The catalog page
          I've
          > > > > > included in the link, is for Stancor Transformers, and item
          > > > number
          > > > > > 928-2170 may do the trick, it's 16 volts center tapped @ 11
          amps,
          > > > > that's
          > > > > > 8 volts @ 22 amps by my feeble mind, and costs $34
          > > > > >
          > > > > > > 928-2170 TGC175-16 B 175 16.0 V C.T. @ 11.00 A 8.0 V @
          22.00 A
          > > > > 3.750
          > > > > > > 3.130 2.880 2.500 2.500 0.380 0.250 33.99 31.69
          > > > > >
          > > > > > http://www.alliedelec.com/catalog/pf.asp?FN=631.pdf
          > > > > >
          > > > > > Anybody else have a good source for this kind of thing?
          > > > > >
          > > > > > Hope it helps!
          > > > > >
          > > > > > Just Bob!
          > > > > ...
          > > >
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