The Hameg HM-304 is a 35 MHz digitally controlled analog oscilloscope made around 1995. I was lucky to get this for 85€, and I really like it! Every setting (with some minor exceptions) can be stored in 6 preset slots and it can also be controlled via RS232. It is NOT a digital storage oscilloscope. With about 5.6kg, It is very light, and I was curious what's inside.
Here's an image of what it looks like (not my unit, mine is way cleaner
![Wink ;)](https://www.eevblog.com/forum/Smileys/default/xwink.gif.pagespeed.ic.cldandycH0.png)
):
![](http://ecx.images-amazon.com/images/I/71ZWSRnxGyL._SL1500_.jpg)
Bottom View: Main Board, shielded input section (haven't taken that one apart because it's soldered) and calibration/component tester section in the upper left region. On the bottom right, you can spot the switching PSU.
![](http://felicitus.org/wp-content/uploads/2014/03/IMG_20140315_141938.jpg)
Mainboard "close up". Sorry for the blurred picture, I don't have my digital camera at hand right now. If you want a hi-res photo of this, please let me know, and I'll do a better pic once my new lab is set up. I was surprised to find SMD components almost completely, which is IMHO surprising for a 1995 vintage scope. There's also an Altera device, probably a CPLD.
![](http://felicitus.org/wp-content/uploads/2014/03/IMG_20140315_141944.jpg)
Board beneath the PSU, not sure what it does:
![](http://felicitus.org/wp-content/uploads/2014/03/IMG_20140315_142118.jpg)
Top view of the case. As you can see, there's barely anything in here. The board on the right-hand side is the
control panel. You can also see the input section, which I haven't torn apart.
![](http://felicitus.org/wp-content/uploads/2014/03/IMG_20140315_142138.jpg)
Rear side behind the tube. They even went through the trouble and designed a plastic cover for the high voltage part. The white thing below seems to be a ceramic hybrid resistor of some kind.
![](http://felicitus.org/wp-content/uploads/2014/03/IMG_20140315_142157.jpg)