[time-nuts] R: Re: EFRATOM LPRO-101

[iovane at inwind.it]

I had exactly the same symptom on one of my units: a comparator circuit fails 
to detect the passing
of the sweept voltage over the upper treshold of about 12.5V. The problem was 
R215 on the bottom face of the pcb, 100K.
Sometimes it is not a matter of budget, at least in my case, and trying to fix 
a faulty device may have the taste of a challenge.
Please check that resistor, and let me know.
(a secondary check before checking R215: after warm-up, say 5 minutes, try 
interrupting the power supply for an instant:
this forces the unit to restart sweeping the voltage, and, being warm, it 
could happen to lock before reaching the 12.5V treshold).

Antonio I8IOV

>Buy another one, they are so cheap :-)
>
>Out of the last lot of five that I bought from the same source, four 
>work very well and one is marginal - sometimes it locks but it's 
>noisy, sometime does not lock.
>Lamp and xtal voltage are ok, but it jumps up and down by 1E10. Very 
>positive overall, IMHO.
>
>73 - Marco IK1ODO
>
>
>At 22.08 02/02/2010, you wrote:
>>Hello all.
>>
>>I received an EFRATOM LPRO-101 last week from eBay Fluke 1, and 
>>wired it up last night. The results are not good.
>>
>>Using a HP 5370B counter with calibration less than one year old, 
>>the frequency reads = 10,000,146,012.9
>>Power Applied = 24.9Vdc @ 0.30 amps after warm up
>>Lamp Voltage = 5.9 Vdc
>>Ext C Field = 2.437
>>XTL V Mon = 14.67
>>Bite = 4.57
>>
>>Bite never goes low.
>>
>>I just sent an email to the outfit I purchased it from, but would 
>>like to get this working instead of waiting a month or so.
>>
>>Is it dead?  Any thing I can do to revive it?
>>
>>Any suggestions?
>>
>>Thanks to all.
>>
>>Jim N0OBG
>
>
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