Re: [tracker2] OT2m defect - poor RX sensitivity problem
- C1 and C2 are mounted differently than r1 d5, ie C1 and C2 are mounted
left to right from the screw, D5 an R1 are mounted vertically. KC0WNY
On 6/1/2011 10:07 AM, Scott Miller wrote:
> You can check if it's affected easily enough - just take the cover off
> and check C1 and C2, near the upper left screw on the PCB when the LEDs
> are facing you. They should be oriented front to back like the other
> components in that row, not side to side.
> On 6/1/2011 6:57 AM, Teddy Banks wrote:
>> I just received one, but I am just an appliance operator.
>> On 5/31/2011 4:11 PM, Scott Miller wrote:
>>> I just discovered that our contract manufacturer made an error in
>>> assembling the latest batch of OT2m boards. They installed capacitors
>>> C1 and C2 incorrectly, and the result is that the boards require a high
>>> (> ~1.5Vp-p) audio level to function correctly. We got the first
>>> portion of the batch assembled and tested just hours prior to Dayton and
>>> didn't catch the problem then because the audio level on the test setup
>>> was too high - they were tested for noise handling but not for low audio
>>> If you bought an OT2m at Dayton or received one in the last week (only 2
>>> or 3 units made it out after Dayton before we discovered the problem),
>>> then it's probably affected by this problem.
>>> There are 3 options for dealing with the defect:
>>> 1. Short solder jumper SJ2. The frequency response will be affected a
>>> bit, but in our testing it hasn't seemed to have any negative impact on
>>> the decode performance. This is the easiest fix and requires only a
>>> soldering iron.
>>> 2. Install the capacitors correctly. C1 should be on the left and C2 on
>>> the right. They were installed with C1 on top (horizontal) and C2
>>> below. This will require a hot air pencil or a steady hand with a
>>> soldering iron.
>>> 3. Send it back to us. You can contact me off-list for an RMA, and if
>>> you're in the US we can send a pre-paid mailing label.
>>> I'm going to try to track down as many Dayton purchases as I can, but we
>>> only have records for credit card purchases. If you know anyone who got
>>> an OT2m at Dayton this year, please let them know.
>>> The test fixture is now set to a very low audio level to check for this
>>> problem, and I'm going to make sure the CM gets their programming fixed
>>> right now. I don't know how they managed to get it wrong on this job
>>> and right on the last one, but they just moved to a new facility so I'm
>>> thinking they might have also switched to a different pick and place
>>> machine and re-entered the program manually.
>> KC0WNY - Ted
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KC0WNY - Ted