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R2001C Motorola Serv monitor
Posted: Mon Mar 06, 2006 4:43 pm
by ABANAKA
Hi all
I posted a message about my R2001C and I had one reply and thanks to that gentleman for his answer. Which was I need to check the power supply Caps. The problem I have is the display before it warms up is in large letters and off the left and right of the CRT. It also has a ripple in the display even after it warms up.
I just need to know which caps I need to change I beleive they are the big ones in the rear. Does anyone have a copy of the Power supply that I get I would pay for a reprint or maybe it could be scanned and sent that way.
Thanks
Mike
Posted: Tue Mar 07, 2006 10:25 pm
by bernie
My two bits worth:
Dave is right in suspecting the electrolytics...He was my mentor in test equipment for the last 30 years or so.
I have a spare manual that I can loan you.
I have developed a "shot gun" treatment for the power supplies in the R2001 B/Cs that I serviced. They very rarely ever come back with PS problems.
Here is where to look for the bad caps.
Motorola, for some reason, used electrolytics from some outfit that was too ashamed to put their brand name on them. These caps cause problems in the UHF MSF CLB stations, as well as the R2001 B & C.
The identifying feature is shiney RED epoxy on the end with a clear insulating jacket. No brand name. The positive terminal leaks, and breaks off, the entire Aluminum can may leak, and blister. If left in place can burn a hole in the board from leaking.
Should you ever find one of these in anything replace it!
In the HV power supply, there are two caps that need to be changed.
Be very careful not to lose the sholder insulators when you open the module. These are the only two electrolytics in the module.
(C-15, 47/50V is the suspect one, change C-21, 100/35 as long as you are in there)
Switching power supplies are VERY rough on filter caps due to RF heating.
In the LV power supply(A-1) there are two modules with these caps:
The output module(A1A2) will have several of these, C213, 1,000/16V,C212, 2200/16 come to mind. ( I replaced all of these in "my" units 20 years ago.)
The switcher module (A1A1) has about 3, this module is somewhat tricky to disasemble, be sure not to lose the sholder washers.
Place a dab of heat sink compound under the switch transistors. The original sholder washers are too thick, so the transistors do not contact the heat sink.
The LV power supply is removed from the bottom of the unit. Be very cautious with the ribbon connectors, the pins are very brittle.
When the unit is apart inspect the pin connections on the two end cards, if burnt replace the pins. Also inspect the cable from the main power transformer for burnt pins. Burnt pins cannot be repaired, they must be replaced, both pin and socket. It is possible to replace individual pins.
(By "repair" I mean scrape the tarnish, and tighten the female contact. Heating anneals the contact)
The unit must be de-gaussed before aligning the A-2 board.
A heavy duty tape eraser also works well. I use a color TV coil.
If this is not done, the display will not stay centered.
Note: 2200UF may not be a stock value at your parts store, use the next highest value. Anything is better than an open, leaky cap.
The CRT is very sensative to external AC fields, which cause "swimming" of the display. (A beat between the vertical scan freq, and the 60HZ AC field. Placing AC powered test equipment on, or very near the R2001 can cause this.
Posted: Wed Mar 08, 2006 3:12 pm
by 440roadrunner
Bernie, there's hardly a post you make that I don't learn something useful. You oughta sit down and write a book--or maybe more than one book.
I think, maybe I'm wrong, would be to sit down and go through some of your monitor service books, and just type out notes--nothing fancy, just this very stuff here about things.
Put it into some document form, and up for sale either here or on eFray.
Posted: Fri Mar 10, 2006 8:22 pm
by DJP126
One thing to add to Bernie's post above. Make sure ALL of the screws that are on the analyzer are tight. I've seen all sorts of "symptoms" cleared up by tightening hardware. This includes "swimming" displays and RF spray at some but not all frequencies.
Posted: Fri Mar 10, 2006 10:17 pm
by bernie
My two bits worth:
440roadrunner, you are too kind. I am afraid that I have very few notes
other than when I went to the depot for informal training..by Dave.
Most of my notes that I have collected over the years deal with obsolete part numbers, which I got from Dave.
I do have some articles that I wrote dealing with site issues, desense, receiver multicoupler optimisation, duplexer tuning. Yours for the asking
So many people have helped me over the years, so I attempt to help when I can. I have made many good friends on BatLabs over the years.
R-2001C Service Monitor Manuals
Posted: Sun Mar 12, 2006 11:47 am
by RandyR
Hi, I'm a new member of the board and the proud owner of a recently adopted R-2001C Service Monitor. I used one of these back in the early 80's and remember it being a top notch unit.
While I remember the basics of using the unit, I really need a manual for the one I have adopted.
Additionally, does anyone still calibrate these beauties?
Any help would be appreciated.
Posted: Mon Mar 13, 2006 10:47 am
by DJP126
Additionally, does anyone still calibrate these beauties?
The Test Equipment Service Depot (now CTDI not Motorola) still has 100% support on the R2001B/C/D series. They can be contacted at 1-800-323-6967. All of the techs there were the Motorola techs so it's only a name change.
Other places I know about that can calibrate the 2001 series are Auburn Electronic Labratory in Auburn, KY and EML in Franklin, TN. I'm sure there are others as well.
Posted: Mon Mar 13, 2006 2:51 pm
by RandyR
Thanks for the response, when I get the unit and manuals, I'll see about a full calibrate. Good to know they're still supported.
Posted: Mon Mar 13, 2006 3:41 pm
by Bruce1807
If you are going to calibtate don't bother fixing it. Just pay fixed rate
about $1350 and it will come back calibrated and repaired.
All parts are covered unless the screen needs replacing (that is extra).
It's a fine unit I still have a 2021 (same series with a few extras)
but you get long arms when you use it for field service and it was a pain
to lug up water towers. Now I have a 2670 with all the bells and whistles including the autotest software for the XTS3000,5000, astro Spectras etc.
It works great.
Posted: Wed Mar 15, 2006 3:45 pm
by RandyR
Thanks for the advice. It should arrive tomorrow, we'll see what it needs then.