[time-nuts] FRSc RB lamp experiment

[paul swed]

Magnus it indeed does look very good.

I have re-assembled the various boards and the system locked up as normal
after the warm up period. I do indeed have a failure in the lamp control
startup crkt.
So I pulled the fet gate Q2 to ground through a 1 K ohm resistor setting the
lamp to 24 volts. After ignition just let it float taking the lamp voltage
to 17 Volts.

The lamp, after ignition is 10 volts when its oven is still cool and has
dropped in brightness. This is normal for the warm up period. Still at
8.5044 volts after the lamp oven gets to 177 degrees.
VCO correction voltage is 6.023v. As I recall, this is mid range on the
voltage.

The reference after warm up and adjusting the c field is down in the 1x10-11
area. Anyhow I adjusted the c field and the systems not fully assembled nor
has it really been stabilized long enough. Was simply curious so I do not
think this is really a very accurate assessment. Especially since this is
time-nuts territory.

By the way I purchased the heat gun from a supplier thats on amazon.com. Its
the NTE or ECG HG300d for $19.95. Two heat ranges 250 degree c and 350
degree c. Small and easy to handle. I used the low range and adjusted the
height of the lamp to the heat gun tip approximately 4" distance to get 300
degrees F.

So next steps is to let the unit cook in or maybe I will further assemble it
and troubleshoot the startup crkt. Add the unlock counter. (A pedometer and
opto coupler) and let the system run for a long while perhaps a week or so
to see what really happens.

Thanks for your guidance and help Magnus. Who would have thought there was a
recovery technique for FRS-c RB references.

Regards
Paul
WB8TSL


On Sun, Feb 13, 2011 at 8:12 AM, Magnus Danielson <
magnus at rubidium.dyndns.org> wrote:

> Paul,
>
>
> On 13/02/11 04:27, paul swed wrote:
>
>> Well pretty good news
>> The lamp voltage went from 1.83 volts a dead bulb to* 8.9 volts a new
>> bulb*.
>> By adjusting the oscillator I can get to 9.6 volts but I know the the
>> oscillator will not start correctly at 82 Mhz its happy at 92 Mhz.
>>
>
> This is good news, for the level of re-assembly you where at.
> The lamp is in the ball-park now...
>
>
> Cheers,
> Magnus
>
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