Hi Martin,
In any case, I wouldn't send the Orion back to Ten Tec if you couldn't
tell them how to trigger the problem. I had a problem with my Omni VII
that was intermittent, and I had a way that I could always make it
happen. I told Ten Tec about this, and they still couldn't find the
problem, even after I returned it to them twice. The unit was a demo
that I had recently bought from them, so they swapped it for another
one, which has been working fine.
73, Tony W1OT
On 9/21/09, Martin Ewing <martin.s.ewing@gmail.com> wrote:
> On Mon, Sep 21, 2009 at 12:16 PM, Dr. Gerald N. Johnson <geraldj@weather.net
>> wrote:
>
>> On Sun, 2009-09-20 at 14:39 -0400, Martin Ewing wrote:
>> > Right, but is there a do it yourself prescription, short of digging in
>> with
>> > the probes and actually trying to *understand* things? (Awful thought!)
>> I
>> > could/will ask TT, but I wonder if anyone has done it out there. (Shame
>> > that there is no repair manual.)
>> >
>> > I can't make the condition appear on command, so that complicates
>> matters.
>> > It's intermittent. Experience (more than I have with the Orion) would
>> > probably help...
>>
>> Often an intermittent can be forced by applying alternate heating and
>> cooling. A hair dryer or hot air gun supplies heat and a spray can
>> product like Freeze-Mist or even the dry air lens cleaners provide cold
>> from the rapid expansion of a compressed gas. Start with a large area,
>> and if that triggers the problem, then cut the area in half, until the
>> part is located. That's called a binary chop when writing a computer
>> program for searching. Half the area previously searched.
>>
>> Then maybe you will find (the circuits are available) that you have hit
>> on a temperature sensitive capacitor part of a VCO and all you need to
>> do is to turn the slug in a coil ten degrees in or out to get it back in
>> range. With the controlled failure induced by heating and cooling, you
>> can soon find which way is an improvement. It is possible to overheat
>> circuit boards with some hot air guns, like those made for paint
>> removal. You don't want that much heat. The $12 hair dryer can be
>> enough.
>> >
>> > 73 Martin AA6E
>> >
>> 73, Jerry, K0CQ
>>
>
> Thanks, Jerry, all good suggestions.
>
> There can't be that many PLL's in the synthesizer chain, so finding the
> circuit probably is not a big problem. The reason I'd hesitate to do trial
> and error is that you could just as easily make things worse as fix them
> without having some guidance on which screw to turn and which test point to
> watch.
>
> I am reminded of the would-be jr. tech who thought he'd help out his dad by
> tightening down all the screws in those funny IF transformer cans. I name no
> names.
>
> In these digital days, it seems strange if circuits are drifting like this.
> I wouldn't be the first to note that some of the Orion boards run rather
> hot, and a cooling fan might have helped prevent some of these issues.
>
> 73 Martin AA6E
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|