[time-nuts] PRS10 case temperature

[Chris Burford]

I see a 42C baseplate temp on my PRS10. I have the newer (U-shaped) heatsink attached. I also have a 70mm fan moving air at a low speed across the the long axis of the heatsink.

The case temp (ad10) as seen by RbMon is generally 67.2C

Chris


---- Scott Mace via time-nuts <time-nuts at lists.febo.com> wrote: 
> I have been experimenting with a PRS10 and using Lady Heather to collect data.  This unit had several failed components in the lamp 
> assembly, which I replaced and the unit locks well now.  One thing I noticed is that on cold startup, the unit seems to think it's 
> already at 40-50C, when in reality it's only slightly above room temperature.  The sensor settles around 79-82C.  I've measured the 
> baseplate and it is around 50C.  I believe that all of the ovens are running slightly low as a result (if I understand the circuit 
> correctly).  I'm thinking that the case temp sensor, a LM45C, on the power supply board is bad.  Anyone else running a PRS10 with 
> reasonably correct baseplate temperatures?
> 
> Here are some of the numbers I'm seeing:
> 
> AD1 - Heater supply : 24.360V
> AD2 - +24V supply: 24.370V
> AD3 - Lamp FET drain: 4.910V
> AD4 - Lamp FET gate: 4.080V
> AD5 - OCXO heater: 1.811V
> AD6 - Cell heater: 2.101V
> AD7 - Lamp heater: 1.513V
> AD8 - Photo signal: 3.831
> AD9 - I/V converter: 4.804V
> AD10 - Case temperature: 80.80 C
>                           ^^^^
> AD11 - XTAL thermistors: 0.961
> AD12 - Cell thermistors: 0.971
> AD13 - Lamp thermistors: 0.972
> AD14 - Freq cal pot: 2.337
> AD15 - Analog ground: 0.005V
> AD16 - TXCO varactor: 7.240V
> AD17 - VCO varactor: 11.520V
> AD18 - Multiplier gain: 11.520V
> AD19 - RF synth lock: 4.900V
> 
> 
> 
> 	Scott
>
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