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Products => Test Equipment => Topic started by: Jwalling on May 14, 2017, 06:48:53 pm

Title: Knock-off Agilent 53131A option -003 prescalers
Post by: Jwalling on May 14, 2017, 06:48:53 pm
Has anyone ever played or tested one of these? http://www.ebay.com/itm/332141807029? (http://www.ebay.com/itm/332141807029?)

Do they meet HP/Agilent/Keysight specification for sensitivity?

Specification is:
-21dBm @ 2.7GHz to 3GHz
-27dBm @ 100MHz to 2.7GHz.

EDIT: Corrected model # in subject line.

Title: Re: Knock-off Agilent 54831A option -003 prescalers
Post by: TheSteve on May 14, 2017, 07:39:59 pm
I have one of the clones, can't say for certain it is the exact one linked. If it isn't it is very very similar though. It works great and meets spec.
Title: Re: Knock-off Agilent 54831A option -003 prescalers
Post by: technogeeky on May 15, 2017, 02:35:13 am
Jwalling:

This looks almost exactly like the product that Shahriar of The Signal Path (https://youtu.be/21_9Dspzu_w?t=6m35s) characterized, tested, and installed in his 53131A frequency counter. Maybe the board he used looks a little better, maybe it has some more vias, but it looks essentially the same.

Let me know if the video is helpful.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: Jwalling on May 15, 2017, 11:48:41 am
Thanks for the link technogeeky. Very useful.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: bingo600 on May 16, 2017, 05:17:46 pm
I have one from a Polish seller , works fine

/Bingo

Ps: Also got one for my PM6680B , from same seller
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: TheSteve on May 17, 2017, 02:54:05 am
BG7TBL has another variation of the clone on ebay now - this one claims to go to 8 GHz. It is the same price as the 3 GHz.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: Jwalling on May 17, 2017, 09:26:02 am
BG7TBL has another variation of the clone on ebay now - this one claims to go to 8 GHz. It is the same price as the 3 GHz.

Not seeing that one, Steve. Do you have a link?
Or is this the one: http://www.ebay.com/itm/HP-AGILENT-53131-53132-53181-8G-Simple-Option-Frequency-Counter-Input-100M-10GHz-/262740237472?hash=item3d2c89dca0:g:MKcAAOSwA3dYXNM0 (http://www.ebay.com/itm/HP-AGILENT-53131-53132-53181-8G-Simple-Option-Frequency-Counter-Input-100M-10GHz-/262740237472?hash=item3d2c89dca0:g:MKcAAOSwA3dYXNM0)
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: HighVoltage on May 17, 2017, 10:07:38 am
I have bought a similar one when I fixed my 53132A counter and it still works perfectly

https://www.eevblog.com/forum/repair/agilent-53132a-repair-(and-possible-upgrade)/ (https://www.eevblog.com/forum/repair/agilent-53132a-repair-(and-possible-upgrade)/)

Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: TheSteve on May 17, 2017, 08:02:09 pm
BG7TBL has another variation of the clone on ebay now - this one claims to go to 8 GHz. It is the same price as the 3 GHz.

Not seeing that one, Steve. Do you have a link?
Or is this the one: http://www.ebay.com/itm/HP-AGILENT-53131-53132-53181-8G-Simple-Option-Frequency-Counter-Input-100M-10GHz-/262740237472?hash=item3d2c89dca0:g:MKcAAOSwA3dYXNM0 (http://www.ebay.com/itm/HP-AGILENT-53131-53132-53181-8G-Simple-Option-Frequency-Counter-Input-100M-10GHz-/262740237472?hash=item3d2c89dca0:g:MKcAAOSwA3dYXNM0)

That is the one. I almost bought one for testing but already have the 3 GHz version. Still it is tempting, guess I could resell my 3 GHz model. I have an 8.4 GHz signal gen so it would pair nicely.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: Nuno_pt on May 17, 2017, 08:50:41 pm
This one would be a good addiction to my HP 53181, instead of the polish 3GHz version.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: Jwalling on May 17, 2017, 09:14:23 pm
wA3dYXNM0[/url]

That is the one. I almost bought one for testing but already have the 3 GHz version. Still it is tempting, guess I could resell my 3 GHz model. I have an 8.4 GHz signal gen so it would pair nicely.

I don't know about that one...
Quote
- Reference input sensitive:200M -5DBM 500M -12DBM 1G-8G -20DBM

Doesn't meet specification (for -030 anyway).

Quote
- Input frequency range: 100M-10GHz

OK.

Quote
- Attention:When no input frequency ,frequency counter there is reading.

I would imagine it's not very stable. Not a big deal.

Quote
- If frequency install 5G or 12.4G option is not suitable install this board(test data is wrong)

Not sure what they're saying there...

I should probably have mentioned at the beginning that this one has a genuine Agilent -030, but it starts to crap out (unstable) at -15dBm with a 3GHz input. Maybe it's repairable?

Thanks.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: TheSteve on May 17, 2017, 09:19:31 pm
Likely is, it's only amplifiers and divider or two. One amp could easily be weak.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: B1nary on October 14, 2017, 08:32:39 pm
On the off chance anyone is monitoring this thread . . . I am a newbie (yes I know),but, i have one of the 8G Opt 30 boards from BG7TBL. It has proven to be totally unreliable. It is also not the most sensitive clone board. Mine has died and all I can get from the seller is that it uses a HMC363 chip in a 8 pin dip package (something I already knew). All my requests for help have gone unanswered and I'm certainly not expert enough to know what wrong with the thing. I can feed it a signal at varying strengths -15dBm up to 0dBm but the counter just continues to read 8.2Ghz (apparently that is normal but it happens to be the only reading the counter shows on Ch 3). If I feed 600Mhz to pin 4 of the HMC362 I don't get anything out of any of the other pins. I tried having the seller send me a schematic so I could blunder my way around but that request has been ignored as well. If any of you here can suggest a method I can try out to verify the HMC362 chip is OK then I can go look for a problem elsewhere. I'll certainly understand if if this is too much of a newbie question to answer but thank you in advance if anyone does help. It's the only way I'm going to learn.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: TheSteve on October 14, 2017, 08:52:26 pm
I guess you don't have an RF probe to verify the signals going in and out?

Maybe start a thread in the repair section and post some good pictures.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: Jwalling on October 14, 2017, 09:19:54 pm
I completely forgot about this thread. Turned out that it was the MB510PF prescaler chip that was bad.  I bought a replacement from hkutsource, and it worked fine.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: B1nary on October 14, 2017, 10:19:46 pm
No I don't have an RF probe (another 'tool' for my to buy list). I used the scope to measure the in/output for the HMC362 chip. and my DMM to see if I had any voltages on it at all. I am suspicious the chip has died. I have 5V on Pins's 1,3, and 4 but nothing  anywhere else. The scope shows the input RF signal on pin 4 but again I don't see anything on any of the other pins. 

I'll go over to the Repair Thread and see what I can find.


I really appreciate your reply.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: texaspyro on October 15, 2017, 12:17:06 am
I have the 3 GHz and 8 GHz (supposedly counts to 10 GHz) ones.  Both seem to work, but I can only generate up to 4.5 GHz.  I only tried the 8 GHz one once when it came in.  The 8 GHz ones are not very sensitive (I've seen mention of -10 and -15 dbm).  It was only $60.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: jadew on August 01, 2018, 12:02:21 am
I just started selling a variant of this 3rd channel options as well. Better sensitivity in the higher ranges than the clones (and the original) and with warranty: https://cojotech.com/hpo-030. There's also a datasheet there, if you want to compare numbers.

I'll soon have a 6 GHz version, but the sensitivity specifications will be different (and the price).
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: blackbird on June 20, 2019, 08:50:52 pm
I'll soon have a 6 GHz version, but the sensitivity specifications will be different (and the price).

Any update on the 6GHz version?
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: jadew on June 21, 2019, 11:42:11 am
Any update on the 6GHz version?

Hello blackbird,

It has taken me longer than I expected to get it done, but it is ready. I was actually supposed to release it 2 weeks ago, but due to delays introduced by the PCB house and DHL, I haven't. Right now I'm waiting for the customs proceedings on the final revision PCBs.

I expect to have them for sale starting with next week (I doubt DHL will delivery them today).

Cheers!


Edit: Btw, one of the reasons for the many delays is that I decided to market it as an 8 GHz option too, because I expect a bit better than -20 dBm sensitivity at 8 GHz (the working prototype on my bench does -25 dBm at that frequency). Anyway, don't rely on these numbers too much, since I might not specify it to these levels - I'll have to build several boards and extract a typical value first.

Edit 2: To put a bit of distance between my version and the Chinese one, I'll make a direct comparison between their specified sensitivity and the sensitivity I get on my current prototype (again, don't take them as final numbers, the final numbers may be worse):

| Frequency | Chinese (dBm) | Cojotech (dBm) |
| --------- | ------------- | -------------- |
| 100 MHz   |               | -14            |
| 200 MHz   | -5            | -26            |
| 500 MHz   | -12           | -34            |
| 1 GHz     | -20           | -39            |
| 2 GHz     |               | -41            |
| 3 GHz     |               | -40            |
| 4 GHz     |               | -38            |
| 5 GHz     |               | -34            |
| 6 GHz     |               | -31            |
| 7 GHz     |               | -27            |
| 8 GHz     | -20           | -25            |
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: blackbird on June 24, 2019, 09:53:29 pm
I've seen the Chinese 4.2 and 8 GHz variations online but nowhere can I find reliable data and reviews. So these go to the 'if nothing else can be found' list. Hence I'm interested in the sensitivity results of your final design, of course the price of the product matters. ;)
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: jadew on June 25, 2019, 04:36:21 am
With a bit of luck, I'll have a datasheet ready today and possibly a presentation video. I'm at the mercy of DHL, which seems to have a bottleneck these days in the customs department (people on vacation maybe?).

Edit:
I've seen the Chinese 4.2 and 8 GHz variations online but nowhere can I find reliable data and reviews.

I've looked for information on those too, but I couldn't find much either. What I did find, were one or two threads on the forum with complaints about the quality.

Edit 2: Just got word on my package, it's going to be delivered tomorrow. I'm almost tempted to just use my previous boards, since this run was for cosmetic reasons only.
Title: Re: Knock-off Agilent 53131A option -003 prescalers
Post by: jadew on June 27, 2019, 08:06:07 pm
@blackbird, https://cojotech.com/media/datasheets/HPO-080%20-%20Datasheet.pdf (https://cojotech.com/media/datasheets/HPO-080%20-%20Datasheet.pdf)

They're up for sale, and I'm running a promotional discount of 15%. Unfortunately, I can only offer them with the SMA to BNC cable atm (more options will be available in the future).

http://cojotech.com/hpo-080 (http://cojotech.com/hpo-080)