HP 54502A scope - Page 1
Forum section: electronics / testgear

author: //Matt//
author_rank: Contributor
timestamp: March 12, 2019, 03:29:47 pm
content: I found a good offer for the HP 54503A scope.Is it any good?An answer would be appreciated.

author: Stray Electron
author_rank: Super Contributor
timestamp: March 12, 2019, 03:35:51 pm
content: Good scope but old and not worth much in this country. Make sure that all of the channel inputs work before buying. Burnt out inputs are common and PSUs are starting to fail due to age. Even an old slow DSO is a big improvement if you've only used an analog scope before.

author: //Matt//
author_rank: Contributor
timestamp: March 12, 2019, 03:40:46 pm
content: Thanks for the reply.Is it true that the bandwidth written on the scopes in this range from HP is only representative of the bandwidth for repetitive signals?

author: //Matt//
author_rank: Contributor
timestamp: March 12, 2019, 03:55:10 pm
content: upsI said the wrong model number it's actually the HP 54502A.

author: dzseki
author_rank: Frequent Contributor
timestamp: March 12, 2019, 04:09:18 pm
content: Quote from: //Matt// on March 12, 2019, 03:40:46 pmBasically yes, but the 54502A is the best one of that family, because it has 400MS/s real time sampling, which is good up to 100MHz single shot bandwidth as they claim, which in 99% of the cases is plenty enough. The only downside of this scope is the relatively small memory (2000pts) which means you may miss high frequency events in the signals.

author: //Matt//
author_rank: Contributor
timestamp: March 12, 2019, 04:57:18 pm
content: I just found an HP 54602B for the SAME PRICE.What would you recommend?

author: dzseki
author_rank: Frequent Contributor
timestamp: March 12, 2019, 07:50:32 pm
content: The 54602 is one generation newer. It has 20Ms/s sampler (2MHz single shot bandwidth) but it has 2 additional channel with limited input range. For the same price I think the 54502 sounds better deal, providing it works flawlessly.

author: David Hess
author_rank: Super Contributor
timestamp: March 13, 2019, 08:08:58 am
content: Even with the slower 20MS/sec sampling rate, I would recommend the 54602 over the 54502 because it supports peak detection. The 54502 has its 400MS/sec maximum sampling rate but with its short record length, it cannot sustain that slower than 100ns/div.I have a Tektronix 2230 with a comparable 20MS/sec performance and peak detection and consider it completely usable for general purpose applications.

author: dzseki
author_rank: Frequent Contributor
timestamp: March 13, 2019, 09:21:48 am
content: Quote from: David Hess on March 13, 2019, 08:08:58 amI found no reference that the 54602 would have peak detect, to my understanding only the better models like 54615/6 had.EDIT: it is indeed have.Also to my understanding peak detect is useful on scopes that have high sampling rate but small memory as they perfom one scan at full sample speed before each acquisition, but if the sampler itself is only running at 20Ms/s there is no way it would detect rapid changes in the signal not even in peak detect mode.I had the HP 54503A (500Mhz repetitive, 20MS/s, no peak detect) that was too a usable scope, but for the same price I still stand by my opinion.

author: //Matt//
author_rank: Contributor
timestamp: March 13, 2019, 01:23:36 pm
content: What about the HP 54520A it goes for some more money but it says that the sampling rate is "1Gsa/s to 500Msa/s". What does that mean? does the sampling rate change somehow based on the settings of the scope?

author: dzseki
author_rank: Frequent Contributor
timestamp: March 13, 2019, 02:27:16 pm
content: So far this is the best. It is again one generation newer.The sampling rate is changing because if only one channel is used then the two AD converters working in „bridged” mode yielding double sample rate 1GS/s, but if both channels are used then the AD converters work simultaneosly at 500MS/s. The memory depth is moderate on these scopes with 32kpts, but has 1ns peak detect.Keep in mind that with digital oscilloscopes the memory depth is a key factor how fast a scope can take the samples in a given time base, meaning even this scope can’t sample the input at 1GS/s at any time. This particular scope can run at 1GS/s roughly up to 2us/div time base, above that the sampling rate decreases, peak detect function is supposed to help in such situations.

author: //Matt//
author_rank: Contributor
timestamp: March 13, 2019, 05:10:46 pm
content: Would you recommend any other decent scope in the rage of 400 GBP.

author: David Hess
author_rank: Super Contributor
timestamp: March 13, 2019, 05:46:39 pm
content: Quote from: dzseki on March 13, 2019, 09:21:48 amIt still applies at slower sampling rates. 20MS/s should detect 50ns peaks and that is what the specifications say. Faster would be nicer of course and it will miss shorter peaks but at least it will be consistent.

author: dzseki
author_rank: Frequent Contributor
timestamp: March 13, 2019, 08:12:34 pm
content: Quote from: //Matt// on March 13, 2019, 05:10:46 pmWell for that money you can have a brand new oscilloscope as well, it really depends on what is your goal with the scope?

author: //Matt//
author_rank: Contributor
timestamp: March 13, 2019, 10:57:10 pm
content: The 400 GBP is an upper limit I would prefer it to bee around 200-300 GBP. All of the used scopes seem to have better specs. There are a lot of great deals in the USA but I am limited to Europe because of the postage and import tax.Is there any decent new scope you could recommend. (minimum bandwidth of 100MHz but preferably higher.)Apretite the help.

author: tautech
author_rank: Super Contributor
timestamp: March 13, 2019, 11:03:56 pm
content: Quote from: //Matt// on March 13, 2019, 10:57:10 pmSDS1202X-E339 Eurohttps://www.siglenteu.com/digital-oscilloscopes/sds1000x-e-series-super-phosphor-oscilloscopes/

author: dzseki
author_rank: Frequent Contributor
timestamp: March 14, 2019, 07:57:25 am
content: Quote from: //Matt// on March 13, 2019, 10:57:10 pmThere is always high demand for oscilloscopes (one never can have enough...) therefore the price is high for used working scopes on popular sites like e-bay. Your only chance would be to find „non-working” scopes for cheap and fixing them up, but this is a gamble.The SDS1202X-E look really nice for the price.

author: //Matt//
author_rank: Contributor
timestamp: March 14, 2019, 01:18:34 pm
content: Thank you for your recommendation!I will consider buying the SDS1202X-E.seem like a good deal for the money and it's new.