[Test-Equipment] Re: Dana 8020B counter

[Alan Melia]

Hi Dave, I dont know that particular, model but the description sounds very
like the the Racal 9024 &  9025s that I have. Dry electrolytics have been a
feature of these over the years. I have had the first 9024 nearly 20 years
now. My finding suggest if the nixies light up and diplay zeros, look to the
gate generation side. Is there a visible 1MHz output from the internal
reference osc? If not try and extrenal 1MHz feed. Is it hum free (you get
really crazy counts when the electrolytics go down and you get hum on the
rails feeding the reference) Next look at the signal down the gate divider
pcb, which is (on the Racal) the easiest to get at and is East-West behind
the input sockets on the panel. I bought a faulty 9025  and it turned out
just to be a duff 7490 in the gate generation divider chain. It is now
working very well and reliably. It had an ovened reference so is very good.

I do have manuals for the Racals, but we would need to swap information off
list to see if they are pertinent to your unit. I can scan some bits so you
can check.

Good luck de Alan G3NYK
alan.melia at btinternet.com


----- Original Message -----
From: <test-equipment-request at mailman.qth.net>
To: <test-equipment at mailman.qth.net>
Sent: 07 July 2004 09:01
Subject: Test-Equipment Digest, Vol 3, Issue 3


> Send Test-Equipment mailing list submissions to
> test-equipment at mailman.qth.net
>
> To subscribe or unsubscribe via the World Wide Web, visit
> http://mailman.qth.net/mailman/listinfo/test-equipment
> or, via email, send a message with subject or body 'help' to
> test-equipment-request at mailman.qth.net
>
> You can reach the person managing the list at
> test-equipment-owner at mailman.qth.net
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Test-Equipment digest..."
>
>
> Today's Topics:
>
>    1. manual for dana counter 8020b ?? (dave)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Tue, 06 Jul 2004 20:42:04 +0100
> From: "dave" <red at redgrass.gioserve.com>
> Subject: [Test-Equipment] manual for dana counter 8020b ??
> To: test-equipment at mailman.qth.net
> Message-ID: <200407062042040720.0037562A at smtp.gioserve.com>
> Content-Type: text/plain; charset="ISO-8859-1"
>
> Hi all. I am searching for a manual / schematic for a frequency counter
DANA 8020B.
> Obviously the prize would be if someone had a copy in electronic form they
were prepared to share. However I am not usually so lucky so anything
considered and obviously I am prepared to pay copying costs etc. (UK based)
>
> I bought it at a hamfest "as is".When I found there was no +5 V rail due
to a failed electrolytic I let myself believe that would be all it needed.
Of course not. The electrolytic was replaced giving a nice smooth 4.95 volts
but there was no difference to the non-working of the counter.
> Nine digit nixie display, all showing zeros. All power rails ok now (+/-
30, +5, +200) .  10 mHz clock running ok, input signal from pre amp / input
board ok into ttl board. Pre scaler on board should allow count to 600mHz so
well worth a bit of effort to get going.
>
> It contains about a hundred mostly ttl chips with a few discretes. Age
about 1976. Two double sided boards impossible to run out of place without
extenders. I must be getting old, because I just can't find my way around
with the scope.
>
> Any help welcomed........thanks    Dave    g8sfu at callsign(dot)net
>
>
>
> ------------------------------
>
> _______________________________________________
> Test-Equipment mailing list
> Test-Equipment at mailman.qth.net
> http://mailman.qth.net/mailman/listinfo/test-equipment
>
>
> End of Test-Equipment Digest, Vol 3, Issue 3
> ********************************************