Low usb Bus Voltage warning

[thetfordjr]

Ok I am not informed on this. I will explain what is happening and hope for some suggestions. I have a SDS 100 and the gps accessory cables. I just also got a new ford 150. two usb in the console of which I believe neither is of 2 Amp or greater. When I hook the gps cables and use the usb I see the gps at the bottom of the screen but later I get the low usb bus voltage warning. I move to a 12 volt usb adapter and i do not see the gps at the bottom. So is my 12volt usb adapter bad. it there a device to measure usb voltage just by plugging in?

 

[wtp]

Amazon.com : usb voltmeter

 

[jonwienke]

You need a 2A USB port to run tbe SDS100. The scanner draws about 750mA, and if you're charging the battery, double that. A 1A port can't handle the load, and many USB cables can't, either.

 

[RadioSc]

If your truck usb port dosen't support 2.0 or greater i would recommend stop using it. Before you damage your scanner. I bought the Duracell and its great. I plug my radio in one slot and my phone in the other slot. And i get no low usb voltages messages. oh yea make sure you using the original charging cable. See the output its 3.1 amps. Just the right amount as your original house wall charger

 

[RadioSc]

View attachment 100753
I have a correction to make this is the one I have my bad. See the output its 3.1 amps. Just the right amount as your original house wall charger

 

[KK4JUG]

I tend to favor Anker products. They're consistently good quality, albeit a little pricier than many others.

 

[RFI-EMI-GUY]

Just FYI most USB chargers, both 12VDC and 110VAC, create a lot of radio noise.

 

[IAmSixNine]

A quality cable will also do wonders to help prevent low usb voltage.
Voltage drops as current increases and if you use a cheap cable voltage will drop even more.

 

[CHHTX]

I tend to favor Anker products. They're consistently good quality, albeit a little pricier than many others.

Just to mention something that's caught my eye is a closely named company but not the same. Aukey is an Anker competitor but in my experience, not as good. Cheaper yes but not as good. I have to confess that I'm an Anker fanboy all the way! They've always worked great for me and haven't had one fail in several years of using a lot of different ones.

 

[gmclam]

1) I use a cigarette lighter to USB adapter in my truck, not the built-in USB, to power the SDS-100. It is rated at more than 2 amps.
2) I use the shortest USB cable I can, and one that is heavy duty.

Even with the above, the radio is too sensitive to the voltage drop. One problem is that the USB voltage is measured at the source connector as being 5.0 volts and can only go down via the cable. It would be nice to use remote sensing, but that's not part of USB. The only real alternative to mitigate this issue is if the SDS-100 can work just fine with oh 4.5 volts and that's where the warning threshold is set.

 

[JoeBearcat]

It would be nice to use remote sensing, but that's not part of USB.

How would that work? If you have a 10% voltage drop in the cable, the voltage at the scanner would be 10% lower than the remote sample voltage. You need to measure the voltage at the scanner since that is what is reaching the scanner.

Yes, quality cables are a must.

 

[AvidHiker]

+1 for Anker, but I'm sure all of those little 12V socket adapters generate some noise. The worst offenders are probably the ultra-small units and super cheap stuff. Not worth the $10 or so you might save.

Just FYI most USB chargers, both 12VDC and 110VAC, create a lot of radio noise.

This guy does pretty extensive testing:

Index of tested USB DC power supplies/chargers (Car chargers)

If cost is no object:

USB Power Converter Plug

aircraft USB charger, USB plug, usb receptacle, FAA USB, FAA iPad charger, FAA approved USB charger, USB charger, power adapter, EFB converter plug, EFB charger, EFb power supply, EFB charger, FAA EFB power supply.

lonestaraviation.com

https://store.harkwood.co.uk/air/#4-port-chargers

 

[KK4JUG]

Quality is certainly important to me but the Lone Star products are a bit of an overkill. As my mother used to say, "Too much of anything is enough." I'll stick with Anker.

 

[sfb88]

There was reference to RFI issues in this thread.

SDS 100 Reception Issue

I ran into a strange reception problem with my Uniden. It may not be specific to the SDS100, but I don't have another radio to test with unless I can get my Yaesu fixed. Here's the situation. I mainly use my SDS 100 in my car. I have the radio's USB charging port plugged in to a Comkia power...

forums.radioreference.com

A Garmin was mentioned in post #19 I think.

 

[djeplett]

I have to add this is one of my biggest pet peeves with this radio. I bought the Uniden GPS setup and after only a couple trips it would constantly say low bus voltage. I mean the number of connects/disconnects had to be in the teens. And no, the connector was not stressed. This was with the Uniden cables and several different lighter adapters, all rated at 2A+. After squeezing the mini USB end it has been better, but still too finicky. I can see if you're trying to charge and use the GPS, but even if you turn "charge while on" off it complains.

 

[KK4JUG]

When traveling, I used Jon's internal GPS with the SDS100. No problems. (I have an SDS200 for the car now.) With the 436, I used an Anker 3A cigarette lighter plug to power the scanner AND the puck. Once again, no problems, and it kept the scanner charged., too.

 

[Ubbe]

... later I get the low usb bus voltage warning.

I have maybe 7-8 different mains to 5v usb adapters and half of them give low bus voltage warning. Those have output voltage below 5.0 volt. I've tried different USB cables and it doesn't matter if I have charge enabled, it doesn't seem to be the voltage drop in the cable that are the problem, it's the 5v adapter that needs to output 5.0v or higher. I have one adapter that gives 5.2v with or without load and that always work, even when charging that adds the total amps to 1.2A

Get a cheap $5 USB voltage/amp meter to check out the actual voltage from USB connectors.

/Ubbe

 

[kittrav]

"After squeezing the mini USB end it has been better ...."

Not to hijack the thread, but I have discovered that my micro USB port stopped powering/charging, unless I apply slight pressure towards the front of the radio.

Anyone else with this issue?

Moderator: please move to new/another thread, if appropriate.

 

[gmclam]

How would that work? If you have a 10% voltage drop in the cable, the voltage at the scanner would be 10% lower than the remote sample voltage. You need to measure the voltage at the scanner since that is what is reaching the scanner.

You can google remote sensing. It works by using 4 wires instead of 2. Two wires carry the load (like they do now) but the other 2 are essentially used to measure the voltage at the load. The source supply increases voltage to overcome the loss so that the voltage at the load is at the desired level.

This is something that would need to be incorporated into USB, not the scanner.

 

[KK4JUG]

For those who wish to really monitor USB voltage, amps, load impedance, etc., try the UM25C. It's less than $30 and has Bluetooth. Below is a shot of the Samsung Galaxy S8 screen with the tester's data. I maintains current information as that information changes. I got mine from Amazon.