Forums :: Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives :: Books
Support This Site: Contributors :: Advertise


It is currently Mar Tue 19, 2019 9:50 pm


All times are UTC [ DST ]





Post New Topic Post Reply  [ 34 posts ]  Go to page Previous  1, 2
Author Message
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sat 09, 2019 7:37 am 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
I grew up in Irvine and visited Dana Point often for family events, so this meter has some relevance to my history. That's partially why I am intrigued by it. Seems fitting to save it from the scrap heap.


Last edited by valley on Feb Sat 09, 2019 3:18 pm, edited 1 time in total.

Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sat 09, 2019 9:04 am 
Member

Joined: Nov Wed 15, 2006 7:56 am
Posts: 1278
Location: germany
I have a Keithley 5900 in use, it is a Dana 5900, relabeled with some cosmetics at the front panel.
A fine instrument ! And inside, you see all IC in socket, I love that !
Martin


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sat 09, 2019 6:30 pm 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
I think I found part of my range selector issues. This is the front most board that has the selector switch wiper assemblies attached. You can see the contacts below the plastic ring. I had hoped this would come apart but I think the plastic would break. Any ideas/techniques for cleaning this? I guess I could get a cue tip into the holes and clean the contacts, but the wiper is facing the other direction so I couldn't get to that.


Attachments:
WIN_20190209_09_24_18_Pro.jpg
WIN_20190209_09_24_18_Pro.jpg [ 179.32 KiB | Viewed 184 times ]
Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sat 09, 2019 6:51 pm 
Member
User avatar

Joined: May Mon 18, 2009 5:55 pm
Posts: 3008
Location: Erie, PA
valley wrote:
Update- I bought the other one. :shock: :lol:


Somehow I knew there was another big heavy rectangle in your near future. :P A very wise idea in order to keep at least one of them alive.

I would just let some D5 Deoxit soak in to that wiper switch for a while, followed by rinsing it out with CRC QD cleaner or 99% alcohol. That should get all that old oxide off and put it back in business without trying to disassemble it.

Dana's discrete transistor boards look more friendly than those Wang used in their calculators during this time which were just intended to be disposable, no gold contacts or anything. Fixing these things today is a time-consuming affair of pulling and testing. I know a lot of guys here hate things with any IC's or processors, but understanding the necessity is clear when you needed over 800 transistors just to make a freaking electronic calculator back in the day.

Image

-Mark-


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sun 10, 2019 3:43 am 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
I may have TWO more giant heavy rectangles coming now :lol: The seller asked if I wanted the 5600 as well. Unfortunately it is missing the test lead assembly so I dont want to pay much for it, I guess ill see if they agree.

I completely disassembled the accessory unit and cleaned every contact surface I could get to. The real surprise was the corrosion on the PCB contacts, they appear to be gold plated but there was definitely some corrosion of some sort on them. Deoxit removed it. They insert a bit easier also.

This process did cure some of the gremlins, notably the blinking/fading decimal light cross talk between ranges. They switch cleanly now between ranges. The problem of continual counting in some ranges remains for the DC and ohms section, the AC section seems OK. Millivolts does not work at all. Ill have to wait for the manual to arrive to start into those.


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sun 10, 2019 4:23 am 
Member
User avatar

Joined: May Mon 18, 2009 5:55 pm
Posts: 3008
Location: Erie, PA
I saw that 5600 used some type of custom test lead connector, it almost looks like the connector for the shielded RF interconnection cable HP uses on the back of the 8566/68 spectrum analyzers to connect the RF deck to the display section. I hate weird nonsense like that, many of the Solartron meter models do the same thing. The lack of the special test lead set is a good bargaining chip on that one. You can probably fabricate something, but it will take some creativity.

Just about all of these early DMM's use a base range on DC, usually the 1V range. Every range above it the input voltage is dropped through resistor networks, and ranges below it the input voltage is amplified. So if DC mV ranges aren't working, likely one of the cards is an amplifier where the problem might be at. Also on digital meters of this vintage, the ohms function is usually 4 wire ohms only, requiring a set of "Kelvin clips" to get it to measure.

-Mark-


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sun 10, 2019 4:41 am 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
I am not familiar with the 4 lead/kelvin clips ohm measuring device. Could you elaborate? Is this something I could fabricate?

Here is what is on the front of the meter:


Attachments:
WIN_20190209_19_36_09_Pro.jpg
WIN_20190209_19_36_09_Pro.jpg [ 161.21 KiB | Viewed 160 times ]


Last edited by valley on Feb Sun 10, 2019 5:40 am, edited 1 time in total.
Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sun 10, 2019 4:55 am 
Member
User avatar

Joined: May Mon 18, 2009 5:55 pm
Posts: 3008
Location: Erie, PA
It looks to be a 4 wire ohms only setup like the HP 3450A/B. Cheap Chinese Kelvin clips like this will work fine: https://www.ebay.com/itm/LCR-Meter-Cabl ... rk:29:pf:0

When you get the manual, the operation of the ohms function will be more explicit, including how to connect the cables to measure resistance. It might not work until you get all the DCV ranges working right first.

-Mark-


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sun 10, 2019 11:26 pm 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
Cubdriver wrote:

Can you post some pics of the display section of yours? It looks very similar at a glance to the face of mine; perhaps they're electrically close, too. If so, I may eventually want to pick your brain on that.

And thank you for buying the second one. I wavered a few times this past week, but managed to resist.

-Pat


What do you need to see in the display section? I have yet to disassemble and clean the display and logic assembly but when I do ill be sure to get some pics.


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Sun 10, 2019 11:36 pm 
Member
User avatar

Joined: Jun Fri 05, 2015 4:59 am
Posts: 294
Location: Southeastern Litchfield County, CT
valley wrote:
Cubdriver wrote:

Can you post some pics of the display section of yours? It looks very similar at a glance to the face of mine; perhaps they're electrically close, too. If so, I may eventually want to pick your brain on that.

And thank you for buying the second one. I wavered a few times this past week, but managed to resist.

-Pat


What do you need to see in the display section? I have yet to disassemble and clean the display and logic assembly but when I do ill be sure to get some pics.


Nothing necessarily in particular, just want to get an idea how close it may be to the 5403 I snagged. And no rush, mine is still sitting out on the left coast as I didn't get a chance to pack and ship it on my last visit out there.

-Pat

_________________
https://pmanning.smugmug.com/


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Mon 11, 2019 2:06 am 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
I attached some pics of the display section of the 5500. I notice there are some differences. On the 5500, the accessory unit has an indicator stack that illuminates based on the selector position, indicating the function (DC, Ohms, etc). On the 5403, this is done on the display itself in place of the 5500s 6th nixie tube. The indicator stack on the 5500 is illuminated by neon lamps buried inside the accessory module, the light is fed to the front panel through glass light pipes, all of which are broken on this example. To see the indicator light you have to peer directly into the hole where the light pipe used to be.

Very interesting. Based on component dates these two models were produced in the same general time frame. It would be interesting to see the advertising catalog for these instruments (if one exists).

In the last pic I tried to capture what I assume are test point sockets. They appear on the null detector, sequence logic, and control logic boards. I think this is an interesting innovation that possibly eliminates the need for card extenders (perhaps?)


Attachments:
WIN_20190210_16_55_08_Pro.jpg
WIN_20190210_16_55_08_Pro.jpg [ 177.53 KiB | Viewed 134 times ]
WIN_20190210_16_55_00_Pro.jpg
WIN_20190210_16_55_00_Pro.jpg [ 247.13 KiB | Viewed 134 times ]
WIN_20190210_16_55_48_Pro.jpg
WIN_20190210_16_55_48_Pro.jpg [ 120.39 KiB | Viewed 134 times ]
WIN_20190210_16_55_21_Pro.jpg
WIN_20190210_16_55_21_Pro.jpg [ 113.47 KiB | Viewed 134 times ]


Last edited by valley on Feb Mon 11, 2019 5:04 am, edited 1 time in total.
Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Mon 11, 2019 2:55 am 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
I see the 5600 sold, the seller and I could not come to an agreement on price. I hope someone here nabbed it.


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Fri 15, 2019 4:27 am 
Member

Joined: Jul Thu 18, 2013 11:29 pm
Posts: 193
Location: Madera, CA
Well..

On my unit, luckily, part of the problem with the ohms section was a fuse. I replaced the fuse and now it is taking readings, however, they are not consistent between ranges. I assume this is partially a calibration issue. I did look into resistance standards and was surprised by the cost, is there an alternate method for calibrating the resistance range? I suppose I could order the highest tolerance resistors I can get and use those, 1% or something?


Top
 Profile  
 
 Post subject: Re: Dana Digital Voltmeter 5500
PostPosted: Feb Fri 15, 2019 6:11 pm 
Member
User avatar

Joined: May Wed 18, 2011 2:40 am
Posts: 3731
Location: Littleton, MA
valley wrote:
I suppose I could order the highest tolerance resistors I can get and use those, 1% or something?

Cheap 0.01% resistors:
https://www.goldmine-elec-products.com/ ... ber=G21118
https://www.goldmine-elec-products.com/ ... ber=G21520
https://www.goldmine-elec-products.com/ ... ber=G21551
https://www.goldmine-elec-products.com/ ... ber=G21101
https://www.goldmine-elec-products.com/ ... ber=G20756
https://www.goldmine-elec-products.com/ ... ber=G23079
https://www.goldmine-elec-products.com/ ... ber=G23081
https://www.goldmine-elec-products.com/ ... ber=G23334
https://www.goldmine-elec-products.com/ ... ber=G23328
https://www.goldmine-elec-products.com/ ... ber=G23330

_________________
Steve Byan http://www.byan-roper.org/steve/steve-at-play/


Top
 Profile  
 
Post New Topic Post Reply  [ 34 posts ]  Go to page Previous  1, 2

All times are UTC [ DST ]


Who is online

Users browsing this forum: easyrider8, Govee, Jim Beckford, Majestic-12 [Bot], upsss and 5 guests



Search for:
Jump to:  


























Privacy Policy :: Powered by phpBB