Homebrew PCBs

I have an old heathkit digital thermometer. It used 1n4149 diodes 2 of them in series to make the temp sensors . the voltage across the diodes changes with temp that seems to be how it works. Might be a little hot in a laminator though for this type of sensor.

 

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: Sunday, January 01, 2017 11:57 AM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Re: Temp upgrades of lam's HOW high is high heat conditions

 

  

Always learning something new here.
1N4148 + LM741 makes a temperature sensor




On 01/01/2017 07:11 AM, 'David C. Partridge' david.partridge@... [Homebrew_PCBs] wrote:

  

It’s a Vivid IP-330 described as having “hot roller” technology.

 

I need to dig it out as I can’t remember what I did to increase the Temp range (probably just changed a resistor in the op-amp circuit that used a 1N4148 as a Temp sensor).

 

Can’t find a parts list …

 

From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com] 
Sent: 31 December 2016 18:11
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] Re: Temp upgrades of lam's HOW high is high heat conditions

 

  

Really? This grabs my attention.
What make and model?
Can you take a picture and share?
Is there an online parts list we can eyeball that shows how concentric heaters are mounted?

 

On 12/31/2016 11:53 AM, 'David C. Partridge' david.partridge@... [Homebrew_PCBs] wrote:

  

But, but the heaters are concentric with the rollers (or at least they are in my laminator) so

stopped/forward/reverse should make no difference.

 

Dave