Owon vs Tektronix - Page 1
Forum section: electronics / testgear

author: dan3460
author_rank: Frequent Contributor
timestamp: November 15, 2015, 08:36:49 pm
content: About 4 year ago I blew up a Panasonic scope I was using for many years. I collect and repair antique radios and I found using a scope makes life easier. Did not have much money at the time so I purchase an Owon D6062V for about $300, similar Tek at that time was double the price. From that time I have found several old Tek scopes, on ebay or Craiglist, which I have repair or waiting to be repaired. One of my finds was Tek 2465 not working, I repaired it and now sits on my bench besides the Owon, I use both of them constantly.I was tinkering with a circuit that put a sine wave at about 22MHz, the Owon has measurements right on the screen and I saw the circuit putting several volts more than the power supply. That was odd and after making sure that the setup and probes where in the right position I decided to connect the Tek. It showed the amplitud of the wave at the value anticipated. So I decided to test the two scopes with my function generator a Rigol DG1022U which goes up yo 25MHz.The amplitud shown on the Tek is steady up to very near the 25MHz when it drops a little. On the Owon once you get past around 10MHz the amplitud starts to increase, gets to a maximum around 20MHz (around 30% more amplitud) then it goes down when approaching 25MHz by 40% with respect to the Tek.On the Owon i'm using a T5060 a 60MHz probe and on the Tek a TP6100 a 100Mhz probe.The Owon supposed to be a 60MHz scope, is this normal?

author: TAMHAN
author_rank: Frequent Contributor
timestamp: November 15, 2015, 08:47:27 pm
content: Now this is really weird, sorry for stating that. Until the more professional analog people chime in, let me - lowly programmer and digital electronicist - fart around town.belowBasically, filters do NOT have a steppy dropoff. Instead, they transmit less and less of the original amplitude as frequency increases. Most oscilloscope vendors claim a 3db bandwidth, aka that signals at the "painpoint" will show with significant weakness compared to the reality. The more expensive the filter, the steeper its dropoff.What really makes me wonder, is that the amplitude "raises" in the stretch between 10 and 20 MhZ. A very asinine filter design might overshoot...but IMHO, such filters are created only if I would design it (I suck at filters).Now awaiting afrom others who know better.

author: nctnico
author_rank: Super Contributor
timestamp: November 15, 2015, 09:44:42 pm
content: I suggest to do the probe compensation adjustment procedure first. There is a 1kHz square wave output on every scope for this purpose.

author: vk6zgo
author_rank: Super Contributor
timestamp: November 16, 2015, 03:49:52 am
content: Without changing anything else,swap the BNC connector end of the probe leads over,so the T5060 is on the Tek,& the TP6100 is on the Owon.If the Tek now shows the effect previously noted,& the Owon doesn't,it is an artifact of your probes.

author: dan3460
author_rank: Frequent Contributor
timestamp: November 16, 2015, 03:10:30 pm
content: Because this is a hobby, every time that I use the scopes I make sure that probes are compensated with the scope that it is attached to.I will swap the probes and make the test again. Will report finding.