I have a chance to pick up a Tektronix 7104 Oscilloscope for only $150. Would this be a good scope for general electronics, home audio, tv repair?

 

That's a good price if it comes with 4 plug-ins. The last time I checked, Tek scope prices were at a local maximum.

It's a 1GHz scope; overkill for the applications you mention. I recall reading somewhere that some of the plug-ins aren't compatible with the CRT in that scope. Probably things like the 7D01 logic analyzer and 7D20 DSO.

 

That's a good analog scope, with a bandwidth higher then you will ever likely need, but that's okay.
It doesn't have the many features of a digital scope, such as waveform one-shot storage, and waveform arithmetic that can be useful.
Just make sure it has at least one vertical and one horizontal plug-in with it.

 

He mentions plugins in the ad but I'm a newb and no nothing about oscilloscopes...yet!
Are probes easy to get?
This is his ad:

Vertical inputs are through two 7A29 plug-ins.
Dual time base. Primary time base is 7B10 with resolution down to 2ns/division.
Delay time base through 7B15 (also 2ns/division resolution).
I also have an extra 7A29 plug-in.
No probes included.

 

He mentions plugins in the ad but I'm a newb and no nothing about oscilloscopes...yet!

Those plugins match the 1GHz bandwidth of the scope.

Before you buy, check the intensity of the CRT. The one in that model degrades faster than the slower models.

Are probes easy to get?

You can use some inexpensive aftermarket probes which are easy to get; but a pair will cost $50-100. Genuine Tek will be significantly more expensive.

For lower frequency work, you can substitute other amplifiers (e.g. dual channel 7A26) and get 4 or more channels.

One other thing to note. The 7A29 has an input impedance of 50 ohms.

 

He mentions plugins in the ad but I'm a newb and no nothing about oscilloscopes...yet!
Are probes easy to get?
This is his ad:

Before I bought my scope earlier this year, I was looking and reading about probes. The Chinese ebay probes that are 25 USD are good for 100 MHz. If they say 300 MHz, 500 MHz, don't bother, they are still only good for 100 MHz max. There are some good thread from a few years ago people testing these cheap probes against brand name probes. So for 100 MHz and lower signals get cheap Chinese probes from ebay for 20-30 USD. For anything else I would start shopping for brand name probes. Anyone looking forward to black Friday deals?

 

You will want to bookmark these:
Tek Wiki (scroll down to 7000 series and its plugins): http://w140.com/tekwiki/wiki/Main_Page
7104: http://w140.com/tekwiki/wiki/7104

 

Anyone looking forward to black Friday deals?

I received 2 emails this morning advertising Black Friday deals. I guess retailers think they can avoid criticism for making employees work on the Thanksgiving holiday if they completely ignore the holiday and start weeks early...

 

So for 100 MHz and lower signals get cheap Chinese probes from ebay for 20-30 USD.

I bought a couple pairs of those type of probes several years ago when I was trading a Tek 7623 for a TV. I tested the pair I traded and kept a pair for myself, but I use genuine Tek and HP probes with my scopes.

 

One other thing to note. The 7A29 has an input impedance of 50 ohms.

That's a big red flag.
You can't used standard probes with a 50 ohm impedance input.
They do make 10x probes for 50 ohm impedance but the impedance is then still only 500 ohms, which is too low for general purpose work.

 

That's a big red flag.

OP should plan on getting some lower frequency vertical amps. 7A26 are good for 200-250MHz; not much price difference from the lower frequency plugins.