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7L14 - no 1st LO output


 

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Hi Guys
Information please. I have a 7L14, where the 1st LO has just died.
It seems the main YIG driver transistor, an NPN Darlington, has already been replaced
The Tek part number is 151-0454-00, but this bears a Motorola number SJ6796 and a date code of 8018.
?
Despite searching all the usual places (net/databooks)?I cannot find any reference to the Motorola part.
Anyone got any information about it they are willing to share?
thanks
Chris HJ


 

On Mon, Feb 11, 2013 at 9:44 AM, Christopher Hilton-Johnson
<chj@...> wrote:



Hi Guys
Information please. I have a 7L14, where the 1st LO has just died.
It seems the main YIG driver transistor, an NPN Darlington, has already been replaced
The Tek part number is 151-0454-00, but this bears a Motorola number SJ6796 and a date code of 8018.

Despite searching all the usual places (net/databooks) I cannot find any reference to the Motorola part.
Anyone got any information about it they are willing to share?
thanks
Chris HJ
You could buy a replacement Tek part:


raymonddompfrank
 

Hi Chris,
My very difficult to read copy of the "Semiconductors Common Design Parts Catalog 1982 identifies this (bottom of page 6-20) as a DTS1010, High(er) voltage NPN in TO-3 case. Specs are here:



Could this be correct?

Raymond

--- In TekScopes@..., "Christopher Hilton-Johnson" wrote:

Hi Guys
Information please. I have a 7L14, where the 1st LO has just died.
It seems the main YIG driver transistor, an NPN Darlington, has already
been replaced
The Tek part number is 151-0454-00, but this bears a Motorola number
SJ6796 and a date code of 8018.

Despite searching all the usual places (net/databooks) I cannot find any
reference to the Motorola part.
Anyone got any information about it they are willing to share?
thanks
Chris HJ


 

开云体育

?
?>?You could buy a replacement Tek part:


Got some already?- but thanks for the tip!
Really more about trying to find information about what appears to be an installed?replacement
?
Chris HJ


 

开云体育

>My very difficult to read copy of the "Semiconductors Common Design Parts Catalog 1982 identifies this (bottom of page 6-20) as a DTS1010, High(er) voltage NPN in TO-3 case. Specs are here:

>


>Could this be correct?

>Raymond


Raymond
Absolutely correct - the original is a DTS1010, but again, thanks for the pointer to the datasheet for that part.
My interest is in trying to get information about the part actually installed as the YIG main coil driver in my (failed) 7L14.
I just want to know if it is supposed to be better/different/was a factory installed replacement etc.
during the 7L14 lifetime (according to my Manual) this board (YIG driver) went theough three iterations (suffix -01 through -03) yet mine is a suffix -00, confusing or what?
Really my interest is in trying to get some data on this Motorola part, to add perspective to this issue, but?I have a correct replacement, which I will use & see what happens!
?
Chris HJ

?


raymonddompfrank
 

Chris,
Your question was clear, both David DG and I didn't read it well.

This is one ref. to a Freescale (-Motorola) part with just a few specs:


Here you can see that the mil-designated Freescale part is considered at least in some way compatible with Tek's part and DST1010 (and some others).

I guess you've seen it already.

--- In TekScopes@..., "Christopher Hilton-Johnson" wrote:

Hi Guys
Information please. I have a 7L14, where the 1st LO has just died.
It seems the main YIG driver transistor, an NPN Darlington, has already
been replaced
The Tek part number is 151-0454-00, but this bears a Motorola number
SJ6796 and a date code of 8018.

Despite searching all the usual places (net/databooks) I cannot find any
reference to the Motorola part.
Anyone got any information about it they are willing to share?
thanks
Chris HJ


 

开云体育

Raymond
The good news is that replacing the Motorola part with the Tek specified item produces a cure & all is good again.
?Probably not relevant but the Motorola part was aluminium, and featherweight, the original part is steel and of substance.?I think the problem was junction heat related, in that there was a direct relationship between length of 'off' time, in days, and 'on' time in minutes, with a minimum of 1 day 'off' to get any 'on' time at all.
?
Thanks for all responses
regards
Chris HJ

?


raymonddompfrank
 

AFAIK, the specific heat capacity of aluminium is much larger than that of steel, but this seems somewhat extreme...

Glad your issue is resolved.

Raymond

--- In TekScopes@..., "Christopher Hilton-Johnson" wrote:

Raymond
The good news is that replacing the Motorola part with the Tek specified
item produces a cure & all is good again.
Probably not relevant but the Motorola part was aluminium, and
featherweight, the original part is steel and of substance. I think the
problem was junction heat related, in that there was a direct
relationship between length of 'off' time, in days, and 'on' time in
minutes, with a minimum of 1 day 'off' to get any 'on' time at all.

Thanks for all responses
regards
Chris HJ


 

On Mon, Feb 11, 2013 at 1:00 PM, Christopher Hilton-Johnson
<chj@...> wrote:
Raymond
The good news is that replacing the Motorola part with the Tek specified item produces a cure & all is good again.
Probably not relevant but the Motorola part was aluminium, and featherweight, the original part is steel and of substance. I think the problem was junction heat related, in that there was a direct relationship between length of 'off' time, in days, and 'on' time in minutes, with a minimum of 1 day 'off' to get any 'on' time at all.
I don't think there's a significant thermal performance difference
between steel and aluminum TO3s.