Having moved up to an 11801 and TDS694, I now have three Type 3 and K213 carts (unclear on the difference) surplus to needs. Two in downtown Boston, one in Waltham. Pick them up and they're yours

Not critical doesn't mean not needed. 4uf and 20nf are rather a long ways apart. The capacitor is bad, replace it. As to why it is needed. The HV oscillator is poor neighbor for other circuits

"At the present time, I can get to my equipment - so, I was wondering did HP put this type of capacitor on their equipment? If so, should each and everyone be replaced? In general, should these be

Tom Lee wrote on 11/7/2020 1:40 PM: Hello-- IIRC, these capacitors featured a metallized-paper dielectric which had a "self healing" property-- i.e., a transient overvoltage that caused a  puncture

How much interest is there for a custom 4041 ROMPack that includes the following:- Program Development ROM1 and ROM2- Utility ROM1- Graphics ROM- Plotter ROM- PROM file system with AUTOLD file I have

I had noticed that the service manuals available on eBay were all for "SN B250000 and up" and my unit is B219220. I have also found differences in the circuit images (not the schematics, the

Jeff, Thank you for clarifying where the Tek recommendation for using WD40 is located. And I am glad that they stated its use for switch contacts – a completely different bird from

Jeff, the bad spots on pots can likely be cleaned up by lots of rotations, even if you can't open them up or get enough oil or cleaner into them. Once you get the shafts to turn easily, rotate them

that's what I thought, but then I don't understand why the dead capacitor killed this circuit. I mean it looks like its just buffering an otherwise DC voltage, and it doesn't seem to have shorted, the

but you let "ECR meter" slide? The worst part is that I looked it up before I posted that, and I STILL spelled it wrong.

Yes, the attenuator boards are a special material - likely polysulfone - for good HF characteristics and low "hook," so don't risk damage with solvents or oils. Also, be very careful in soldering and

Well, it's too late for me to not have used WD-40 now, but I'll take whatever comes. The WD-40 seems to have done a good job of loosening up the channel #2 pot, but hasn't made much difference in the

With all the oils and lubricants being mentioned I feel I need to reiterate something that is stated in the service manuals..DO NOT USE ANY lubricants on the scopes high frequancy attenuator switch

Regarding WD-40, I would not recommend it for small or fine parts and mechanisms, except as a last resort to free up things that are seriously seized up. On heavier machinery, it's great for a quick

Colin, You simply REFUSE to believe what I have tried to tell you - It is virtually impossible to get email through to your domain. I am not alone. OTHERS have told me the same thing. This has been

Minor nit (sorry to be picky): It's double-h, double-f in Kirchhoff. (can't help it; it's an occupational hazard) -- Cheers, Tom -- Prof. Thomas H. Lee Allen Ctr., Rm. 205 350 Jane Stanford

HP used (and still uses) RIFA caps, but they weren't the only one. Apple used them, for example (and perhaps still does). My first Mac (a Plus from the late 1980s) had one, and it exploded

I have communicated very recently with Dennis. I did not sense that anything is wrong. DaveD -- This email has been checked for viruses by Avast antivirus

Does anyone have any idea if Dennis Tillman is still ok? I was having some conversation with him a little while ago, but he has gone quiet since I gave him another email address for me in a PM.He

Jeff: Don't be mislead slightly by the removal of the 465 vertical preamp board in the eevblog tear down. The 475 vertical board differs in that the attenuator switches and BNC front panel connectors