• Chip ID

    From Cursitor Doom@21:1/5 to All on Sun May 21 11:07:38 2023
    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the
    schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell. The board it comes
    from is dated 1970, so unless you're an old geezer, you won't
    recognize it anyway.

    https://disk.yandex.com/i/N1dGB_EIUYbf6A

    --- SoupGate-Win32 v1.05
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  • From Cursitor Doom@21:1/5 to All on Sun May 21 11:57:04 2023
    On Sun, 21 May 2023 11:07:38 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    Hi all,

    Anyone seen one of these before? The IC itself has four bjts

    Correction! Apparantly there are *5* BJTs on this chip (U973 on the
    schematic) - and being as this is a 14 pin chip, there's a pin short!
    Weird.

    Here's the section of the schematic:

    https://disk.yandex.com/i/DZTlhbFA0XTE1w

    --- SoupGate-Win32 v1.05
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  • From Cursitor Doom@21:1/5 to All on Sun May 21 17:44:26 2023
    On Sun, 21 May 2023 11:31:52 -0500, Chuck <chuck23@dejanews.net>
    wrote:

    On Sun, 21 May 2023 11:07:38 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the >>schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell. The board it comes
    from is dated 1970, so unless you're an old geezer, you won't
    recognize it anyway.

    https://disk.yandex.com/i/N1dGB_EIUYbf6A
    This will probably replace it. https://www.ebay.com/itm/125671758106

    Well, you've had more luck than I did with that part number. My
    searches threw up nothing at all.
    The IC you've linked to may well be a suitable replacement, but that's
    not really what I was curious about. The encapsulation is white and
    has something mounted on top of it. I'd be interested to know why it's
    white and what the disc-shaped object on the top is. As far as I can
    tell, this white chip is not the original. The original resembles the
    one you linked to. So.... what's the deal with the white encapsulation
    and the disc thing on top of this usurper?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Chuck@21:1/5 to All on Sun May 21 11:31:52 2023
    On Sun, 21 May 2023 11:07:38 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the
    schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell. The board it comes
    from is dated 1970, so unless you're an old geezer, you won't
    recognize it anyway.

    https://disk.yandex.com/i/N1dGB_EIUYbf6A
    This will probably replace it. https://www.ebay.com/itm/125671758106

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Steve Goldstein@21:1/5 to All on Sun May 21 18:09:47 2023
    On Sun, 21 May 2023 17:44:26 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    On Sun, 21 May 2023 11:31:52 -0500, Chuck <chuck23@dejanews.net>
    wrote:

    On Sun, 21 May 2023 11:07:38 +0100, Cursitor Doom <cd@notformail.com> >>wrote:

    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the >>>schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell. The board it comes
    from is dated 1970, so unless you're an old geezer, you won't
    recognize it anyway.

    https://disk.yandex.com/i/N1dGB_EIUYbf6A
    This will probably replace it. https://www.ebay.com/itm/125671758106

    Well, you've had more luck than I did with that part number. My
    searches threw up nothing at all.
    The IC you've linked to may well be a suitable replacement, but that's
    not really what I was curious about. The encapsulation is white and
    has something mounted on top of it. I'd be interested to know why it's
    white and what the disc-shaped object on the top is. As far as I can
    tell, this white chip is not the original. The original resembles the
    one you linked to. So.... what's the deal with the white encapsulation
    and the disc thing on top of this usurper?

    It could be a hermetically-sealed ceramic package. The die would have
    been mounted inside a cavity, wire-bonded to the leads, and then the
    lid soldered or weled on in an inert atmosphere. Back in the day
    plastic packages were notoriously bad in terms of moisture resistance
    and hermetic packages ruled where reliability was needed.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From whit3rd@21:1/5 to Cursitor Doom on Sun May 21 23:33:20 2023
    On Sunday, May 21, 2023 at 3:09:37 AM UTC-7, Cursitor Doom wrote:
    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell. The board it comes
    from is dated 1970, so unless you're an old geezer, you won't
    recognize it anyway.

    RCA made transistor arrays in DIP packages; the white ceramic dates it
    from the early days, but plastic DIPs might still be in production.


    https://disk.yandex.com/i/N1dGB_EIUYbf6A

    the schematic section (pin numbers) is consistent with CA3046 and CA3045.
    The CA3045 was the ceramic-package variant, but specifications are very similar (CA3045F was the brown-ceramic frit seal package, you've got the CA3045 with white ceramic).
    The IC has five, not just four, transistors.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From whit3rd@21:1/5 to All on Sun May 21 23:38:56 2023
    On Sunday, May 21, 2023 at 11:33:23 PM UTC-7, whit3rd wrote:
    On Sunday, May 21, 2023 at 3:09:37 AM UTC-7, Cursitor Doom wrote:
    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell

    Oh, the thing on top is the lid; it's grounded (to pin #13, which is to be
    held non-positive with respect to other connections, it's the IC substrate).

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cursitor Doom@21:1/5 to All on Mon May 22 10:06:26 2023
    On Sun, 21 May 2023 23:38:56 -0700 (PDT), whit3rd <whit3rd@gmail.com>
    wrote:

    On Sunday, May 21, 2023 at 11:33:23?PM UTC-7, whit3rd wrote:
    On Sunday, May 21, 2023 at 3:09:37?AM UTC-7, Cursitor Doom wrote:
    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the
    schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell

    Oh, the thing on top is the lid; it's grounded (to pin #13, which is to be >held non-positive with respect to other connections, it's the IC substrate).

    So it's possible to pop it off? Wow. Never come across one of those
    before. Be interesting to take a look inside....

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cursitor Doom@21:1/5 to All on Mon May 22 10:08:12 2023
    On Sun, 21 May 2023 23:33:20 -0700 (PDT), whit3rd <whit3rd@gmail.com>
    wrote:

    On Sunday, May 21, 2023 at 3:09:37?AM UTC-7, Cursitor Doom wrote:
    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the
    schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell. The board it comes
    from is dated 1970, so unless you're an old geezer, you won't
    recognize it anyway.

    RCA made transistor arrays in DIP packages; the white ceramic dates it
    from the early days, but plastic DIPs might still be in production.


    https://disk.yandex.com/i/N1dGB_EIUYbf6A

    the schematic section (pin numbers) is consistent with CA3046 and CA3045.
    The CA3045 was the ceramic-package variant, but specifications are very similar
    (CA3045F was the brown-ceramic frit seal package, you've got the CA3045 with white ceramic).
    The IC has five, not just four, transistors.

    Yes, it has five transistors (I did correct myself earlier on up the
    thread). However, it's a 14 pin package and 5 BJTs require 15
    connections!

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cursitor Doom@21:1/5 to All on Mon May 22 10:11:59 2023
    On Mon, 22 May 2023 10:08:12 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    On Sun, 21 May 2023 23:33:20 -0700 (PDT), whit3rd <whit3rd@gmail.com>
    wrote:

    On Sunday, May 21, 2023 at 3:09:37?AM UTC-7, Cursitor Doom wrote:
    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the
    schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell. The board it comes
    from is dated 1970, so unless you're an old geezer, you won't
    recognize it anyway.

    RCA made transistor arrays in DIP packages; the white ceramic dates it
    from the early days, but plastic DIPs might still be in production.


    https://disk.yandex.com/i/N1dGB_EIUYbf6A

    the schematic section (pin numbers) is consistent with CA3046 and CA3045. >>The CA3045 was the ceramic-package variant, but specifications are very similar
    (CA3045F was the brown-ceramic frit seal package, you've got the CA3045 with white ceramic).
    The IC has five, not just four, transistors.

    Yes, it has five transistors (I did correct myself earlier on up the
    thread). However, it's a 14 pin package and 5 BJTs require 15
    connections!

    Ignore that! I've just spotted they've internally tied together the
    emitters.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Jeff Liebermann@21:1/5 to All on Mon May 22 10:34:50 2023
    On Mon, 22 May 2023 10:11:59 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    https://disk.yandex.com/i/N1dGB_EIUYbf6A

    The full TEK part number is 156-0065-00 <https://4gte.com/products/tektronix-156-0065-00-transistor-array/>

    If you don't care about reliability, you can probably just replace it
    with 5 TO-92 transistors. Just shove the leads into the 14 pin
    socket. If you want thermal tracking in the differential pair (U973A
    and B), use matched TO-18 packaged devices and some insulating thermal
    glue to hold them together.

    This stuff should work for good insulation, high thermal conduction,
    and moderate ease of removal is you screw it up: <https://cht-silicones.com/products/adhesives/neutral-cure-rtvs-adhesives>
    You could also use it to glue the transistor leads to the IC socket,
    but it would be difficult to remove if you change your mind.

    Good luck.
    --
    Jeff Liebermann jeffl@cruzio.com
    PO Box 272 http://www.LearnByDestroying.com
    Ben Lomond CA 95005-0272
    Skype: JeffLiebermann AE6KS 831-336-2558

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Cursitor Doom@21:1/5 to All on Wed May 24 18:25:40 2023
    On Mon, 22 May 2023 10:34:50 -0700, Jeff Liebermann <jeffl@cruzio.com>
    wrote:

    On Mon, 22 May 2023 10:11:59 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    https://disk.yandex.com/i/N1dGB_EIUYbf6A

    The full TEK part number is 156-0065-00 ><https://4gte.com/products/tektronix-156-0065-00-transistor-array/>

    If you don't care about reliability, you can probably just replace it
    with 5 TO-92 transistors. Just shove the leads into the 14 pin
    socket. If you want thermal tracking in the differential pair (U973A
    and B), use matched TO-18 packaged devices and some insulating thermal
    glue to hold them together.

    This stuff should work for good insulation, high thermal conduction,
    and moderate ease of removal is you screw it up: ><https://cht-silicones.com/products/adhesives/neutral-cure-rtvs-adhesives> >You could also use it to glue the transistor leads to the IC socket,
    but it would be difficult to remove if you change your mind.

    Good luck.

    Thank you, Jeffrey, you're a credit to Usenet!

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From legg@21:1/5 to All on Thu May 25 08:49:43 2023
    On Mon, 22 May 2023 10:06:26 +0100, Cursitor Doom <cd@notformail.com>
    wrote:

    On Sun, 21 May 2023 23:38:56 -0700 (PDT), whit3rd <whit3rd@gmail.com>
    wrote:

    On Sunday, May 21, 2023 at 11:33:23?PM UTC-7, whit3rd wrote:
    On Sunday, May 21, 2023 at 3:09:37?AM UTC-7, Cursitor Doom wrote:
    Hi all,

    Anyone seen one of these before? The IC itself has four bjts on a
    single die according to the schematic, but - again according to the
    schematic - there's no connection for whatever this thing mounted on
    top is, which resembles a very thin button cell

    Oh, the thing on top is the lid; it's grounded (to pin #13, which is to be >>held non-positive with respect to other connections, it's the IC substrate).

    So it's possible to pop it off? Wow. Never come across one of those
    before. Be interesting to take a look inside....

    Also might be interesting to buy a CA3045 and fix the damn thing.

    Are you even sure it's failed?

    RL

    --- SoupGate-Win32 v1.05
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