If all else fails, do check with Paul at Tentec Service.
73
Bob, K4TAX
>
>
> Thanks for the reply Bob. I was using the cabinet as gnd.  I will
> recheck voltages in the morning and use the board its self as gnd,or the
> negative dc input as gnd.
>
> That board is a bummer to get out,but I'll do what I need to do. Roger on
> the shotgun method. again thanks ea 73
>
> de nf4r Dave
>
>
>
> ----- Original Message -----
>
>
> From: "Bob McGraw - K4TAX" <RMcGraw@Blomand.net>
> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> Sent: Sunday, March 24, 2013 8:46:50 PM
> Subject: Re: [TenTec] Need help with corsair ii
>
> With voltages like that, it somewhat indicates that the elecrtolytics may
> need replacing. Â These are the coupling caps between stages. Â If the IC
> output drifts negative then the IC is reversed polarized a few mV and
> will
> eventually go bad, become leaky thus give an indication of incorrect
> voltage
> on the following stage. Â Interesting that all of your voltages are high
> as
> compared to what they should be. Â Are you sure you are measuring from a
> true
> DC ground point? Â If not, then that could explain the error.
>
> I am not aware of any item that I could say specifically "change this
> part"
> and it will correct the problem. Â The challenge is to find the defective
> component and change it. Â I don't advocate just changing parts to see if
> it
> fixes the problem. Â More often than not, using the shotgun approach to
> replace parts will introduce more issues than one started with.
>
> 73
> Bob, K4TAX
>
>
>
>
>
> ----- Original Message -----
> From: <nf4r@comcast.net>
> To: "." <tentec@contesting.com>
> Sent: Sunday, March 24, 2013 3:01 PM
> Subject: [TenTec] Need help with corsair ii
>
>
>>
>> I am told that my corsair ll has low audio while on the air. Was using
>> my
>> 705
>> mic.,have also tried my heil mics,with same reports. Both of these mics
>> work
>> fine on my paragon. Corsair was purchased from a friend that had not
>> used
>> it for
>> 3 or 4 years. sn. is 580 02129. I am no tech but have used schematics
>> to
>> troubleshoot and did some homebrewing. Problem is I only have a foggy
>> idea
>> of
>> what I am doing. Traced mic input to audio processor board and found
>> u2a,on pin
>> 3 has 3.7v instead of .9 and pin 5 of u2b also has 3.7v instead of .9
>> and
>> pin 6
>> has 4.1v instead of 1.0. On u1 pin 5 has 2v instead of 0. This is where
>> I
>> get
>> lost and foggy. I have replaced the vfo with the n4yg board but can't
>> see
>> where
>> it should cause my problem. I know the small electrolytic
>> caps go bad but not how to check them. This my first post so am sure I
>> did not give all information needed.
>> Thanks for any help or insight. You can reply to nf4r@comcast.net
>> de nf4r Dave
>> _______________________________________________
>> TenTec mailing list
>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>>
>
>
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