Is there an inexpensive WWV (only) audio receiver? - Page 1
Forum section: electronics / rf-microwave

author: Peabody
author_rank: Super Contributor
timestamp: November 24, 2018, 03:23:53 pm
content: I'm trying to think of ways to sync multiple local audio recordings for later mixing into a podcast. This would be instead of trying to record the Skype conversation itself. And I wondered if the WWV broadcast might be used to mark the beginning and ending of each local recording, so that everyone would be marking at exactly the same time.I have a cheap NOAA weather radio that just receives the local station, and thought there might be something like that for WWV, but can't find one.As an alternative, are there inexpensive "radio-controlled" clocks that sync to WWV? Or are there WWV receiver modules that could be included in a project?

author: Richard Crowley
author_rank: Super Contributor
timestamp: November 24, 2018, 04:02:50 pm
content: WWV (at ANY frequency) is a poor substitute for GPS here in the 21st century.GPS is orders of magnitude more reliable for casual, portable use than WWV.You did not mention what you are recording on? Some portable audio recorder?If you are recording on a computer, then resetting the computer time using NTP seems ideal.It is far easier, cheaper and faster than WWV or even GPS.

author: radar_macgyver
author_rank: Frequent Contributor
timestamp: November 24, 2018, 06:43:18 pm
content: If you are recording digitally, then use NTP to sync each local computer's time, and rely on the timestamps embedded into the recordings.For analog recording, WWV might work. The canonical way to detect it is using a PLL, something like the LM567.

author: edavid
author_rank: Super Contributor
timestamp: November 24, 2018, 07:27:27 pm
content: Radio Shack used to sell WWV receivers that were called Time Kubes or Time Cubes. They do turn up on eBay:https://www.ebay.com/sch/i.html?_from=R40&_nkw=radio+shack+time+kube&_sacat=0&rt=nc&LH_Complete=1However, they don't work very well, especially indoors. I think the problem is the antenna.There are a lot of cheap "shortwave" radios currently available, but I don't know how much you have to spend to get a decent one.All of the "radio controlled" or "atomic" clocks you can buy sync to WWVB, which would work fine.But if you are using Skype, it probably makes more sense to just have everyone use NTP sync, as mentioned.

author: cdev
author_rank: Super Contributor
timestamp: November 24, 2018, 10:46:34 pm
content: If you look around you can find USB GPS dongles for sale for $10 or less. NTP however won't sync to them without 1PPS. A hack that can fool your NTP into thinking it has a real 1PPS with a USB GPS is to connect the 1PPS on the module (verify its there with a scope) to the pin on the USB-UART converter that signifies DCD which is usually left unconnected. (I dont know why they don't do this, as it would make a lot more sense to connect it up)This usually involves some soldering, and it may be difficult to do but Ive been able to do it a number of times with different GPSs and have it stick. Use very thin wire and anchor it well so it doesnt come off - this works best if you use kapton tape, hot glue or silicone to glue it down well- then putting the plastic case back on tightly- well shut or I guarantee you you will soon dislodge your bodge wire by making even the slightest movement.Also note the USB GPSs usually have a built in ceramic patch antenna that usually works much better over a ground plane, oriented with the antenna pointing up, rather than floating in thin air stuck in the jack on the back side of a computer, often sideways. It doesn't have to be big, an old CD works well and is large enough.To use it properly make sure the top of the USB GPS is pointing up and permanently attach the USB GPS to a USB extension cable so you can place it in an appropriate location. (If you want a small improvement in location precision also add a split noise suppression ferrite bead to the USB cable right where it leaves the USB GPS, however this isn't really necessary in the timing application as whatever precision you might otherwise gain in timing is likely lost simply by your use of USB).Some masking tape can tape the USB GPS to the old CD/DVD so that the antenna is kept parallel to the ground plane, (positioned right over the center of the CD and facing straight up) . This will give you a source of time sync thats accurate to at least 1/10 of a second but quite possibly an order of magnitude or more better on a lightly loaded machine.