Discuss Recommendation for oscilloscope requirements in the Service | Support forum.
I’m about to start the replacement of the convergence ICs on an older Panasonic RP-HDTV. As part of the repair, ...

**old_panny** · **01-31-10, 03:13 PM**

I’m about to start the replacement of the convergence ICs on an older Panasonic RP-HDTV. As part of the repair, I was looking to acquire an oscilloscope for this and other electronic troubleshooting project. I have the service manual for the RPTV that shows various waveforms at other test points on the boards.
I have searched for a couple of hours, but have been unable to find multiple sources about what would be the general bandwidth reqts for a suitable oscilloscope to verify the convergence IC repair and general TV troubleshooting? The only thing I have found is:

>>>> Basic requirements are: dual trace, 10-20 MHz minimum vertical bandwidth, delayed sweep desirable but not essential. A good set of proper 10X/1X probes. Higher vertical bandwidth is desirable but most consumer electronics work can be done with a 10 MHz scope. A storage scope or digital scope might be desirable for certain tasks but is by no means essential for basic troubleshooting.

Is there a general formula that should be used for this situation? E.g. the HDTV rates at maximum are 1920x1080 pixels/frame, 60 frames/sec, ????/pixel => yyy Mhz in a oscilloscope to adequately troubleshoot.
Bob

**lcaillo** · **01-31-10, 08:17 PM**

For convergence and deflection circuits you can get by with virtually any scope, as the rates are in the kHz. For signal related work I would want 60mHz or better for analog, and a higher bandwidth storage scope for serious digital work, though I doubt that you will be doing much of either.

**glaufman** · **02-04-10, 09:00 AM**

Len, do you have, or know anyone who has, experience with the USB scope devices, such as the DSO-2090?

**lcaillo** · **02-04-10, 06:42 PM**

They have very limited bandwidth and I would be careful about ground loops and voltage limitations, as well as the low resolution. I have one but its use is limited.

**glaufman** · **02-04-10, 07:55 PM**

I've seen other models with 100MHz BW and (I think) 2G sampling... I think they were still under $400.... any better options for a cheapskate?

**lcaillo** · **02-04-10, 10:06 PM**

I have not seen that kind of bandwidth that cheap.

**glaufman** · **02-05-10, 10:13 AM**

Well... I was wrong about the # of samples, but unless I'm missing something, the BW stands... this is what I've found for less than $400... granted, to get that price you have to buy on ebay form a source in China...

DSO2090, 40MHz, 100MS/s "realtime", 32K samples/ch
DSO2150, 60MHz, 150MS/s "realtime", 32K samples/ch
DSO2250, 100MHz, 250MS/s "realtime", 512K samples/ch
DSO5200A 200MHz 250MS/s "realtime" 1M samples/ch

Discuss Recommendation for oscilloscope requirements in the Service | Support forum. I’m about to start the replacement of the convergence ICs on an older Panasonic RP-HDTV. As part of the repair, ...

Discuss Recommendation for oscilloscope requirements in the Service | Support forum.
I’m about to start the replacement of the convergence ICs on an older Panasonic RP-HDTV. As part of the repair, ...