rf explorer signal generator combo experiences - Page 1
Forum section: electronics / rf-microwave

author: rfguy2020
author_rank: Contributor
timestamp: October 04, 2023, 09:25:09 am
content: Hi,I'm looking for generic RF signal generator. Maximum frequency should be around 3GHz. I would like to use generator for amplifier measurements (IP3, compression point, etc) and other basic measurements. For two tone test, I would actually need two generators.I have been looking for used lab equipment such as E4421B, 8648C, SMIQ03, etc. Those seems to be above 1000€ price range, which is a bit above my budget.I have been looking for RF explorer signal generator combo. I have not found too many reviews about it. I have seen that previous version of signal generator was not very good in terms of harmonics. Is it somehow comparable with old HP/Agilent/R&S equipment?

author: mehdi
author_rank: Regular Contributor
timestamp: October 04, 2023, 08:50:01 pm
content: If you're looking below 1000€, you don't have many options:1. ERASynth Micro: IMHO the best RF signal generator in its price range, but unfortunately not manufactured anymore.2. tinySA Ultra's generator mode: it's really a spectrum analyzer, but also provides an RF signal generator mode (amplitude can't go beyond -18dBm)3. moRFeus: can only generate 0dBm signals4. RFExplorer Combo: awful UI, amplitude can be wrong on some frequencies, not so good phase noise, but actually very good THD (they have really fixed the harmonic issue)[you can also see some tests I made on these devices herehttps://x.com/mehdi0x61/status/1657418754534387713?s=20and herehttps://x.com/mehdi0x61/status/1708532932229390524?s=20]If you can go a bit beyond your budget, you can get either Windfreak SynthHD Mini, or a used GenComm GC747A which is not only a signal generator, but also a VNA and spectrum analyzer and power meter in one device.By the way, I have all these generators (except Windfreak). If you have specific questions or need specific measurements, let me know.QuoteAbsolutely not. (poor phase noise, inaccurate amplitude level, unclean output, ...)

author: rfguy2020
author_rank: Contributor
timestamp: October 05, 2023, 05:50:56 am
content: Thank you for comments and suggestions.1. I think I found that ERASynth is not very good in harmonics? I don't remember the source. It is not option, since it is not available.2. -18dBm is a bit low for amplifier measurements.3. No amplitude control?4. According to specification it has typical phase noise -125dBc/Hz 1M at 1GHz. ERASynth is way better, but it is a bit difficult to judge, because RFexplorer specification gives only one number.Unfortunately, I was not able to see your measurement results in X. I guess you need to register?Anyway, I think I will continue searching old Agilent/R&S equipment and I hope to find good deal.

author: mehdi
author_rank: Regular Contributor
timestamp: October 05, 2023, 07:38:33 am
content: QuoteLet me copy them here:Here's the THD (I measured it with my Signal Hound BB60D analyzer)SignalHound VSG60A: 0.3%MoRFeus: 12.9%tinySA Ultra: 14.1%ERASynth Micro: 14.7%GenComm: 17.9%RFExplorer: 0.7% at 0dBm, and 1.3% at -20dBm.Here's the amplitude accuracy (see the attached screenshot from Excel)I chose 6 frequencies between 35MHZ and 6GHZ, and measured the output once for -30dBm and once for 0dBm, on each signal generator.I used both Anritsu and Mini Circuits power meters.QuoteI'd be surprised to see an Agilent/R&S RF siggen priced below 1K ! (but I hope I'm wrong and you can find a good deal)

author: rfguy2020
author_rank: Contributor
timestamp: October 05, 2023, 09:50:48 am
content: Someone said in this forum that he bought 8648C for £400 and 8647A for £300 from ebay, which sounds pretty good deal to me. It seems that most used equipment are above 1000€ in ebay today.