12580Re: [tracker2] OT2m defect - poor RX sensitivity problem
- Jun 1, 2011C1 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
> Yahoo! Groups Links
KC0WNY - Ted
- << Previous post in topic