SDS150: Dreaded Solder Joint?

[Bmacs]

I have a 1-week old SDS 150 that I have been very happy with up until now.

I had been using it at home with the stock antenna and it was pulling in signals very well.

Over the weekend, I plugged it into the truck antenna (using the Uniden supplied SMA to BNC adapter). It wasn't picking up much in the truck, but I assumed it was just "Sunday quiet" on the radio waves.

Today, I've had the chance to put my SDS100 (stock antenna) next to my SDS150 (stock antenna)... bad news...

The SDS150 is reading consistently 28-30 dB less on RSSI. The SDS100 is picking up all the usual signals - even down to -95 dBm or below (in an office environment) - but the SDS150 is quiet. The SDS150 can only pick up signals in the town that I am.

It may be that plugging in the adapter over the weekend stressed an already weak solder joint.

I'll be testing the two radios side-by-side with a calibrated signal generator later tonight.

Just a head-up for you SDS150 owners.

Bill

 

[tvengr]

Take a look and check if you see ATT on the display. You may have accidentally turned on the attenuator.

 

[Bmacs]

Take a look and check if you see ATT on the display. You may have accidentally turned on the attenuator.

On EVERY channel? I wish it was that!

 

[dave3825]

Have you tried the sds100 antenna on the 150?

 

[mc48]

Check the profile>Miscellaneous>General Options>Global Attenuate.

 

[Bmacs]

Check the profile>Miscellaneous>General Options>Global Attenuate.

I downloaded the profile from the scanner just to double-check if something was borked. The global attenuator is OFF

Have you tried the sds100 antenna on the 150?

Yes - same result.

 

[werinshades]

Send it in to Uniden Repair since it's still under warranty and let us know what they repair.

 

[Bmacs]

Send it in to Uniden Repair since it's still under warranty and let us know what they repair.

I would have loved to just return it to Amazon - I even waited for a WEEK to buy the DMR/NXDN keys... One day later, the thing goes deaf... sheesh...

 

[werinshades]

I would have loved to just return it to Amazon - I even waited for a WEEK to buy the DMR/NXDN keys... One day later, the thing goes deaf... sheesh...

I got it, but probably had something to do with your antenna connector or along those lines. We can speculate for 40 pages here (as I'm sure we will), but your best bet is to fill out a Uniden Repair Form, ship it to them, then when they send it back let us know what they found. The "cold solder joint" issue usually resulted in different symptoms on the 100.

 

[jasonhouk]

I have advised UJE & UAE, we are following this thread. If they respond to me, I'll advise.

 

[Ubbe]

If the signal level are less attenuated in the 800MHz band compared to VHF then it can be a solder joint that have cracked and works as a capacitor. If there's no evident difference then the preamplifier in it has died, probably from static electricity. Seems to be a very common things with Uniden scanners. The repair note would then say that they have replaced Q2, or perhaps Q1 or Q3 depending on how they number their transistors.

/Ubbe

 

[Bob1955]

I have a 1-week old SDS 150 that I have been very happy with up until now.

I had been using it at home with the stock antenna and it was pulling in signals very well.

Over the weekend, I plugged it into the truck antenna (using the Uniden supplied SMA to BNC adapter). It wasn't picking up much in the truck, but I assumed it was just "Sunday quiet" on the radio waves.

Today, I've had the chance to put my SDS100 (stock antenna) next to my SDS150 (stock antenna)... bad news...

The SDS150 is reading consistently 28-30 dB less on RSSI. The SDS100 is picking up all the usual signals - even down to -95 dBm or below (in an office environment) - but the SDS150 is quiet. The SDS150 can only pick up signals in the town that I am.

It may be that plugging in the adapter over the weekend stressed an already weak solder joint.

I'll be testing the two radios side-by-side with a calibrated signal generator later tonight.

Just a head-up for you SDS150 owners.

Bill

Bmacs- Send back your 1-week-old Bearcat SDS150 for a replacement or a refund before your return window runs out.

 

[ADKLove]

I have a 1-week old SDS 150 that I have been very happy with up until now.

I had been using it at home with the stock antenna and it was pulling in signals very well.

Over the weekend, I plugged it into the truck antenna (using the Uniden supplied SMA to BNC adapter). It wasn't picking up much in the truck, but I assumed it was just "Sunday quiet" on the radio waves.

Today, I've had the chance to put my SDS100 (stock antenna) next to my SDS150 (stock antenna)... bad news...

The SDS150 is reading consistently 28-30 dB less on RSSI. The SDS100 is picking up all the usual signals - even down to -95 dBm or below (in an office environment) - but the SDS150 is quiet. The SDS150 can only pick up signals in the town that I am.

It may be that plugging in the adapter over the weekend stressed an already weak solder joint.

I'll be testing the two radios side-by-side with a calibrated signal generator later tonight.

Just a head-up for you SDS150 owners.

Bill

If you should attempt a repair as i did make sure to desolder the charge wires to charge pins and remove the sd card.. Also have to take the retaining nuts off sma and multiknob and its a very tight fit to remove all... I resoldered the center pin of the sma to the fine wire that comes off the receive board.. FWIW "mine was due to a 5 ft drop on antenna port"

 

[Bmacs]

Bmacs- Send back your 1-week-old Bearcat SDS150 for a replacement or a refund before your return window runs out.

I believe that I will lose the keys that I purchased because they are not transferable...

 

[dmfalk]

When returning the unit to Uniden, make sure to mention you have these keys!

 

[Bmacs]

If the signal level are less attenuated in the 800MHz band compared to VHF then it can be a solder joint that have cracked and works as a capacitor. If there's no evident difference then the preamplifier in it has died, probably from static electricity. Seems to be a very common things with Uniden scanners. The repair note would then say that they have replaced Q2, or perhaps Q1 or Q3 depending on how they number their transistors.

/Ubbe

I think you're onto something Ubbe,

Observing all day today - VHF is deaf as a doorknob... 440 MHz is mostly deaf, and 800 MHz is only about 10 dB down - signals are still receivable.

I agree - sounds like a broken solder joint, either center conductor or grounds

 

[buddrousa]

Could it be when you twisted the adapter on you broke the center pin joint? I have not had or seen a problem and I use the adapter every day with an outside antenna. I know it stinks but send it back and let us know the fault.

 

[bearcatrp]

Am hoping this is user error instead of the dreaded cold solder joint crap the SDS100 went through. As mentioned above, send it in since it’s under warranty.

 

[Bmacs]

Ok Gents... Here are the results of my controlled testing... and I am befuddled.

I used a calibrated HP Signal Generator set to 140 MHz, 450 MHz and 858 MHz. 3 KHz dev FM modulated 1 KHz tone (I don't have a method of generating P25). Squelch on both radios set to 2. The radio was connected to the sig gen with a coax cable.

At 140 MHz - the SDS 150 was full quieting at -115 dBm, the SDS 100 was a little scratchy.
At 450 MHz - the SDS 150 was full quieting at -115 dBm, the SDS 100 was a little scratchy.
At 858 MHz - the SDS 150 was scratchy at -115 dBm, the SDS 100 didn't break squelch.

NOT what I expected, but the data is the data.

So I did some over-the-air testing at low power. The SDS 150 performed better than the SDS 100 (both signal quality and RSSI) with the Uniden supplied antenna (from both radios), as well as the Remtronix aftermarket antenna.

So I cannot explain why, all day today, the two radios sat next to each other, the SDS 100 hearing 155.2 MHz full quieting with 5 bars, and the SDS 150 tuned to the same channel not even breaking squelch. This was a P25 simulcast signal (yes - I moved them around all day to see if it was a positioning issue). The same was true for a 447.725 MHz repeater - the SDS 100 receiving DMR clearly and NO BARS on the SDS 150!! As I mentioned in post #16, 858 MHz was within 10 dB of each other on RSSI and they were both receiving.

Maybe there is an intermittent solder joint? and the adapter sometimes happens to tweak it the wrong way??

Like I said... befuddled...

 

[Ubbe]

Maybe there is an intermittent solder joint? and the adapter sometimes happens to tweak it the wrong way??

Like I said... befuddled...

If you can't see the problem while testing with a signal generator then Uniden will neither. So be careful with this issue as Uniden will do just a quick test and then say no fault found, check your antenna, and send it back.

/Ubbe