[time-nuts] Wavecrest DTS 2070

[Ed Palmer]

Hi Marki,

On 9/9/2013 12:15 PM, Mark C. Stephens wrote:
> Amazing Ed, I just had a invasive discography last Thursday!
> I have been a bit quiet because of a back injury too.

You're creeping me out Marki!

> We must be living parallel lives, fortunately my telly is still good, my 9 year old son has discovered Dr. Who so we are having great time watching it :)
> Some of the original series are a hoot :) so overdone but the Dalek's back then couldn't fly...

I remember watching it when it was new in the early '60's.  Scary.

> Only 1000 for a crown, It would be cheaper for me to fly to Canada to get crown
> My last crown was disaster as a result the clown that put the crown in stuffed up and the crown snapped off at the root
> So added to the $2400 for the crown, I am now up for around 7K for an implant.

Geez, I hope I don't follow in your footsteps!  Your 'parallel lives' 
comment now has me really worried.

> The standby PSU tranny is dead short, zero ohm as compared to the 2v/6A supplies 8-10 ohm.
> Any idea what that 2V supply is for?,

Sorry, no clue.  But my mainboard has a +2.1 volt test point so there's 
certainly a 'family resemblance' between our units.  Mine must generate 
the +2.1 volts on the mainboard.

> If I can lose the 2 linear PSU, I'll lose a ton of weight, but possibly at the expense of electrical noise.
> I was thinking that is why they used optics between the control board - to keep spurious noise to a minimum.

Yes, but I would have thought that optoisolators would have been cheaper 
than optical transmitters, receivers, and cables.

> Yeah, I did play roulette by powering it up like that but I was a tad annoyed as I was told it was a working unit.
> The bottom board on this one has millions of tiny surface mount caps mounted on there sides.
> It looks terribly fragile. Much of a job to get it out?

Well, I described my process in the teardown.  Is your board similar?  
Other than the front panel stuff, board removal is just a matter of 
unplugging connectors and unscrewing the mounting screws.

> All the PSU screw heads are under it (of course)

Yup.  I needed to get at the mounting screws for the cardcage so that I 
could inspect the motherboard.

Ed

> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Ed Palmer
> Sent: Tuesday, 10 September 2013 1:53 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] Wavecrest DTS 2070
>
> Sorry, the oracle is out of the office today - I'm the janitor.  :)
>
> I see you've already replaced the 24V supply and powered the unit up.  I would have removed all output connections on the supplies and tested them seperately.  Are you sure about that transformer short?  Remember that primaries on decent size line transformers only have something ike
> 2 to 4  ohms resistance at most.  I wondered why yours was 12 lbs heavier than mine.  Linear supplies - that would do it!
>
> The expanded/exploded capacitors could be just from age, or they could be from an output fault on the power supply that caused the voltage to go high.  That's why I would have tested both power supplies offline.
>
> You said it's alive, but you haven't mentioned if it actually works.
>
> By the way, it turns out that I paid dearly for my good luck with the repair of my 2077.  In the two weeks following that, I got a pinched nerve in my back that's still giving me trouble, I broke a big chunk off a tooth and am now scheduled for a crown at a cost of about $1000, and my big-screen TV died! :(
>
> Ed
>