Hi Roger, I tried the things you mention and I get no hint of a trace. The RESET button's light is never on. Thanks, Barry - N4BUQ

I was mistaken. The 630NA is NOT listed - just the 625NA, 630, and 630A. Thanks, Barry - N4BUQ

Dave, I see an "HVP 2" file. That manual mentions using that probe with a Triplett 630NA on the 500V scale. Unfortunately, I'm not sure what the model number is for my probe. I've never found

Barry, Following from Albert's suggestion that Lockout may be preventing the sweep from starting, can you try the following. Select a slow sweep speed eg 0.5 seconds /div. With a suitable trigger

The manual for the EICO HV probe is on BAMA (boat anchor manual archive) google it .It lists the various resistors in the probe depending on which input resistance VTVM you have. I think the file is

Ignacio, Thanks for that information. I might make an adapter with an appropriate resistor to complete a proper 1000:1 divider. For now, I think I'm okay with the 90M string with the 10M input to

The odd ratio is because these probes were designed for analog VTVMs. These meters had an input resistance of 9 MOhm and used an 1 MOhm series resistor inside the X1 probe, making a  total of 10 MOhm

I have a dpo7254 that has issues , booting issues where scope freezes and I would also like to change to a ssd drive , can soneon tell me where I can get a copy of the original disks that come with

Yes, ignore the non-terminated result -- it's confounded by uncontrolled transmission line effects. When you do terminate properly, notice that you get measurements that are independent of the

Checking again: The Leo Bodnar pulser is giving me 5.4nS at 1.7VP-P on Channel 1 and 2 on the 60MHz TDS210. So basically spot on (a tiny bit over performing, which is nice). If I terminate it into 50

Barry, Nothing stands out yet what is the problem. Start checking d-c voltages. Something will be off. This is what I would do. I see R313 is to a switched voltage. See if you get the -15V on one end

I can confirm that the tube is a direct transplant however I do not know about the HV board. I used a 5110 to replace in the tube in one of my 577's no modification needed. Zen

Mark, No need to apologize! I have benefitted from your advice here many times and would not think you're trying to mislead anyone. I'm sure I could have given more information that would have

Cleaning the contamination everywhere, and replacing the pots in the 577 HV driver did not fix the display, so I managed to get a rackmount 5110 at auction. It has a crisp stable display. Looking

Barry, I apologize for the mistake I made in the diagnostics. I went by the initial statement and previous problems I had. Albert is is right about asking about TP725. Thank you Albert about

Hi Barry, Yes, this activates the trigger lights, but just to be sure I asked you about TP275. So TD CR262 is no longer suspect. The reason for TD CR299 not firing can also be that Lockout is active

Albert, I'll have to check but I think I recall that TP275 is correct - or, at least, shows a waveform similar to what's shown on the schematic. I presume that's what's allowing the TRIG'D lamp to

Folks, Risetime and bandwidth are related by a simple relation: BW= 0.35/ risetime. For a 350 MHz bandwidth, the risetime needs to be 1nS. For a 60 MHz bandwidth, you should expect a 5.83 nS

By the way, I've been assuming that you're properly terminating both pulsers. Improper terminations can make a big difference. (I didn't pay close attention to the thread, so sorry if this was already

Barry, the collector of Q266 should show just a weak signal because Q273 is driven common base. What is TP275 showing? Albert