Yeah the guys normally wear a badge but if your email isn't hidden I will send you my contact details.

Its not hidden TC

One of the things with the CRO is that it is not the easiest thing to use as you have to be able to interpret & understand what it is showing you. I have a 539 that I got for $30 with books & two original probes. It needs one pot replacing which will be a bit fiddly as the shaft needs drilling for a link.

I use a CRO for alignment as they are more sensitive. You have to watch the modern ones as a lot of modern equipment cannot handle the voltages of Valve Radios.

Also applies to meters: Some RF, & Digital meters are useless for accuracy if the voltage etc is erratic, or dirty. That relates to the fact that they sample, average, & then present the info to the display, not directly like an analogue meter.

Also check the old meters internally. There have been a couple given to me, some of mine & others where caps have failed. The most recent when examined had a shunt with all of the silk burned(mostly off). No way that was going to be right.

Marc

GTC, trouble is Sydney is a good 4Hr drive for us and my wife would not handle the trip very well as she has Rheumatoid Arthritis unless we make a weekend of it. Makes things expensive then.

Clive, I appreciate your situation given your circumstances. Wasn't suggesting that you make a 4 hour trip; just reporting my observation about old CROs not being very popular here.

The guy who brought the big one that he had to take back home told me that he has access to many such Tectronix models but won't bother bringing them anymore as there is apparently zero interest in them.

All cool GTC, I appreciate the info.

I have a Telequipment S23A but it is very limited frequency wise but better than nothing.. I would not quibble over size and weight for something with a much higher spec unless it was one on a trolley like we had at AWA, you needed 2 people to carry it if not on the trolley. Maybe I need to put a special order in.

I would not quibble over size and weight for something with a much higher spec unless it was one on a trolley

This one was trolley material. Big and heavy, 1970s style. I don't recall the model number but it also needed a refurb (manual supplied).

I have a Tektronix 2246A on a trolley but, truth be told, I use my $70 Dick Smith CRO more often simply to see if a circuit is oscillating or not.

It is at times amazing to see how things have progressed in reverse. I have a modern Jaycar CRO that I use for most work and the BWD.

It is interesting that the Jaycar one gets to a terminal frequency & dies. Yet the old Heathkit with far less active components, probably due to TV tubes like 6BL8 that can go to several hundred Meg just loses resolution as it goes way past the frequency it is quoted to work at.

Its a bit like the Mediaeval signal fires that needed to be on top every hill to be anything like effective & Digital phone transmitters that also need to be on every hill to be effective.

Marc

Hey guys just a reminder the next HRSA meeting in Canberra is on the 9th January at the scout hall in Hovea Street, O'Connor. 10 am start. Its not an auction its a buy swap or sell. See you all there.

I note that N 5O1 meter has an instruction book. Does that have the circuit? One of the Radio Club guys here bought one at a TAFE surplus sale & it is a dead as a Dodo.

Meter movement is OK so I suspect that one of the little darlings has done something evil & wiped out the chip?

Marc

I will take a look for you. I am at work atm

Thanks! After a day of interruptions & I still have to fix the shower as the head on it broke(?) only put there April 2013 when the house was built. Pretty ordinary for an inanimate (set & forget) item.

However, I did get back to the meter as it is a fixer. Of all the crazy things, the OP amp is powered by two AA batteries, in a chamber inside, & soldered to the printed circuit that forms the lid.

Why???? would you solder that sort of battery in? Beggars belief.

Marc

Marc Email is sent