Help with techtronix 465B scope what to do

[Radio Fox]

Originally Posted by sam67

...So now i am stuck with my scope and wondering what i can actually test with it without an isolation transformer lol is it ok to test the STEREO AUDIO AMPLIFIER IC without one as there are no high voltages being used in my speakers as they are only desktop ones...

I assume the amplifier uses a seperate plug mounted power supply. You will be fine probing your amplifier without an isolation transformer.

Connect the earth lead from the probe to the common point of the amplifier (usually the -ve supply), & look at various parts of the amplifier with the probe tip. If you are going to probe the actual pins of the I.C., be careful not to short out adjacent pins.

[PlainBill]

Originally Posted by sam67

Hi PlainBill,

Thanks for the link ,i did come across that isolation transformer but did not have a clue whether or not it would work with my scope ..So if i buy this is this all i would need to be able to use the scope for most testing or would i need anything else ..Just thought i would ask as i don't mind buying this but don't want to find out that i then need some think else..

Much appreciated .

Thanks
p.s sorry forgot to ask how your cataract surgery went ,my mother in-law said it helped here a great deal.

That isolation transformer would allow you use your scope safely on any piece of electronics that requires up to about 1000 watts. The only additional thing you would need would be a suitable cord and outlet.

The surgery came off quite well. I can see well enough with my 'fixed' eye that I no longer need glasses to use the computer. Driving is a chore because the two eyes haven't learned to work together very well, and my depth perception is off. Fortunately, it's in the 'safe' direction. Other cars and objects appear closer than they actually are. My only regret was I didn't have both eyes done at the same time.

PlainBill

[sam67]

Thanks Radio Fox ,yes i did mean differential probe lol ..

Just had to edit my post as PlainBill is back on line..Thanks plainBill for your time and understanding.

Best

sam67

Glad that you are getting better i know it took my mother in law a while to get right but she said it was well worth the wait.she actually made the mistake of only having one eye done but went back a few months later to sort the other one out.

[sam67]

I have just emailed the seller regarding the Isolation Transformer and will know doubt be buying it ..just to clarify things ,so if i buy a power cord ,i plug the Isolation Transformer into the wall outlet and then plug in the device i am testing i.e monitor,tv e.tc. into the Isolation Transformer and my scope in another outlet ? sorry for the dumb questions but it's only easy once you know how lol.

Best

sam67

[PlainBill]

Originally Posted by sam67

I have just emailed the seller regarding the Isolation Transformer and will know doubt be buying it ..just to clarify things ,so if i buy a power cord ,i plug the Isolation Transformer into the wall outlet and then plug in the device i am testing i.e monitor,tv e.tc. into the Isolation Transformer and my scope in another outlet ? sorry for the dumb questions but it's only easy once you know how lol.

Best

sam67

That's exactly right. It's a good idea to do this when working on any piece of equipment that might have a live chassis. It is vital to do it when working on the input side of an SMPS power supply.

PlainBill

[stj]

an isolated probe has a transformer in it with 1:1 ratio so that the ground-clip on the probe is not physically connected to the ground

[sam67]

I'd just like to thank everyone for helping me along ,i know it's took quite a few posts for me to understand lol but at least i will be able to use the scope safely ..I know i have quite a long journey to go (using the scope correctly) and will know doubt need further advice but i will be be doing a bit more reading up on my scope to get more of an understanding .Hopefully my thread might let someone else see that there is a bit more to a scope than just plugging it in and off you go testing.

Especially someone who is a newbie like myself.I only stumbled upon this great site and then found myself wanting to learn about electronics as i have always liked to take things apart and try to figure out what is wrong ( thats how i learned how to repair and service all the cars i have had and friends also) The good thing with electronics you are not in a cold garage in the freezing cold (that's if you are lucky and have a garage lol).

I have the electronics bug now so there's no turning back.

Thanks once again

Best

sam67