BG7TBL, Leo Bodnar or Other GPS/GNSSDO/GPSDO 10MHz Ref - Page 1
Forum section: electronics / testgear

author: TheBay
author_rank: Unknown
timestamp: June 29, 2021, 10:04:32 pm
content: Birthday approaching and my other half wants to get me some test equipment.I've always wanted a decent 10MHz reference for the workshop but I am suffering information overload and been reading far too much!I'm basically torn between a flavour of the BG7TBL or the Leo Bodnar Precision GPS Reference Clock.I know that the BG7TBL devices have a OCXO and the Leo Bodnar models have a TCXO but whether that makes a difference to my use case I don't really know.Looking at the BG7TBL devices I have no idea what is what and where/who to buy it from.I like the look of the LCD version, but then there is the choice of the GPS or GNSS model? (I'm based in the UK)On top of that there are multiple date revisions and I have no idea what the OXCO is in them, I guess that might be pot luck.Any advice on what BG7TBL version/model(GPS/GNSS?)/seller is best would be really helpful.I initially want a 10MHz reference for my bench equipment, such as the frequency counter, rf signal generator and AWG.I also want a 24MHz reference for SDR's and LNB's but this part is not a deciding factor of which one to go for as I can generate a 24MHz signal from a 10MHz reference or get another GPSDO. So I'm really focusing on getting the 10MHz side sorted first.One minute I want the BG7TBL and the next minute I want the Leo, really can't decide.Also looking on Aliexpress I saw some others called "TM4313" and "TM5101" but I can't find any information on those anywhere.Cheers.

author: duckduck
author_rank: Frequent Contributor
timestamp: June 29, 2021, 11:19:33 pm
content: Quote from: TheBay on June 29, 2021, 10:04:32 pmPrice difference is not huge. It's your birthday. Get the Leo Bodnar. Documentation and support from a UK-based manufacturer that has a web site with firmware updates, support email address, and UK phone number vs. ebay seller / AliExpress makes this a no-brainer.EDIT: Looks like Leo Bodnar offers refunds for 2 weeks if unsatisfied and a 2 year transferable warranty.EDIT EDIT: I have relatives in Wales. It's a beautiful place full of kind, witty people.

author: Bud
author_rank: Super Contributor
timestamp: June 29, 2021, 11:21:48 pm
content: Agreed.

author: TheBay
author_rank: Unknown
timestamp: June 29, 2021, 11:23:01 pm
content: Thanks for the reply.The BG7TBL actually costs more than the Leo Bondar when I factor in VAT, Customs and Shipping costs (Plus the courier customs processing fees). The LCD version could work out to be £200 or more.

author: bdunham7
author_rank: Super Contributor
timestamp: June 29, 2021, 11:47:06 pm
content: I would think that for most practical uses, the Bodnar unit (the larger, GBP 150 priced model) would be far superior. I don't have one, but if I decided I needed a more precise frequency reference than I have now, I'd get it without hesitation based on reputation and my experience with other Leo Bodnar products. I'm not knocking the BG7TBL dude, but other than the verbose display that lets you gloat over the ppb accuracy of your 10MHz signal, it has far fewer useful features.

author: Ringmodulator
author_rank: Regular Contributor
timestamp: June 30, 2021, 10:52:44 am
content: The Leo Bodnar unit can be configured for different output frequencies. For example, my marconi 2955 comm tester requires 5MHz ext input.Afaik, ther are some limitations so that not all frequencies can be cleanly generated.The BG7TBL GNSS versions utilizes an U-blox gps module. This can be configured with the u-center software to use up to 3 sat families out of GPS, Beidou, Gallileo and Glonass at the same time. But beware, there are several variants of the BG7TBLs on the market. They can only 10 MHz and are preset for sine or sqare output.Chris

author: theHWcave
author_rank: Regular Contributor
timestamp: June 30, 2021, 12:19:01 pm
content: I have the Mini Precision GPS reference clock (£100) from Leo Bodnar and its perfect for my purpose. Most of the time I used it to just create a very stable and accurate 10 MHz signal for my frequency counter but it can actually create almost any frequency between 400 Hz and 800 MHz. So far I have not found any that it could not generate but it is true that due to the way the SI5328C is programmed some frequencies cannot be produced, but those must be really odd ones. It uses the MAX-M8 which can do up to 3 GNSS concurrently (GPS, Galileo, GLONASS, BeiDou)Some pics of my unit

author: TheBay
author_rank: Unknown
timestamp: June 30, 2021, 12:49:01 pm
content: Thanks all, my mind is now made up and at ease, I will give my other half the link to the 2 models on the Leo Bodnar site and hopefully I end up with one of them on my birthdayIt will be much easier for her to order from Leo Bodnar than Aliexpress (She's never used it) so that is also a relief!

author: hpw
author_rank: Frequent Contributor
timestamp: June 30, 2021, 05:11:11 pm
content: Quote from: TheBay on June 29, 2021, 10:04:32 pmIf you need a clock distribution, as multiple parallel outputs, so the Bodnar would not fill the requirements.While paralleling BNC load and each with 50E load, some will not have the required signal strength.Also no PN (phase noise figures) given for those clock distribution amplifiers. Target of those is 10MHz even with optional clock source as may a GPS related gear. So Bodnar & Clock distributions as BG7BL the step by solution.>> BG7TBLon Ali, there are various models of BG7TBL, all with unknown OXCO source, so you have to ask while as soon you open other OXCO brand is given. It gets all day with cheaper oscillators.The point of BG7TBL, I do not see a clear given support, only some chicas who deals with the goods and no glue about anyy electronic parts.so BG7TBL real web side is IMHO missinghp

author: TheBay
author_rank: Unknown
timestamp: June 30, 2021, 08:10:01 pm
content: Thanks for your reply, I didn't mention this in the first post but I will build a 10MHz distribution unit or modify an old composite video distributor.If I end up with the dual output Leo Bodnar I will run 2x 10MHz for now, 1 for the frequency counter and the other for the AWG or the RF Gen.That is the big worry with the BG7TBL from Aliexpres/eBay, it could be a "Lucky Dip" with the OCXO and whether the Ublox is a clone or genuine.Quote from: hpw on June 30, 2021, 05:11:11 pm

author: randymatt444
author_rank: Contributor
timestamp: February 04, 2023, 11:04:43 pm
content: I wonder about using it for audio sampling rates (44.1 - 96 kHz) . . jitter?