IF Tuning Cans Question
 

I have a receiver with some ferrite tuning coils in the IF. In the
process of retuning, attempting to peak the IF, I cracked coils in two
cans and they are locked into place. They are in same position from
original and the receiver seems fine, makes sensitivity etc. Is there
any measurable change to the inductor Q or other parameter when this
occurs? I did get replacements but the effort to replace seems difficult.
--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P

IF Tuning Cans Question
 

On Mar 31, 2:34�pm, RFI-EMI-GUY wrote:
I have a receiver with some ferrite tuning coils in the IF. In the
process of retuning, attempting to peak the IF, I cracked coils in two
cans and they are locked into place. They are in same position from
original and the receiver seems fine, makes sensitivity etc. Is there
any measurable change to the inductor Q or other parameter when this
occurs? I did get replacements but the effort to replace seems difficult.

There is PROBABLY no difference.

Assuming the usual "455 KHz" IFT, the cores are most probably
POWDERED IRON in a binder, not "ferrite." Ferrite is iron powder
alloy that
is sintered (heated to not quite liquid state) and thus holds itself
together
without any polymer (plastic) binder.

Ferrite cores and structures will produce different results if broken
than the
manufacturer's data but cannot be predicted. In general, powdered
iron
cores already have their powder "broken" by suspension in the binder
and
can be glued/cemented together without undue change.

Ferrite things have been used in the microwave region for about 50
years
and, for uniformity/reproducibility, require the things to be unbroken
to achieve
the desired results. But, that is in the region of 1 GHz and above
and doesn't
apply to the typical IFT.

73, Len AF6AY

IF Tuning Cans Question
 

AF6AY wrote:
On Mar 31, 2:34�pm, RFI-EMI-GUY wrote:
I have a receiver with some ferrite tuning coils in the IF. In the
process of retuning, attempting to peak the IF, I cracked coils in two
cans and they are locked into place. They are in same position from
original and the receiver seems fine, makes sensitivity etc. Is there
any measurable change to the inductor Q or other parameter when this
occurs? I did get replacements but the effort to replace seems difficult.

There is PROBABLY no difference.

Assuming the usual "455 KHz" IFT, the cores are most probably
POWDERED IRON in a binder, not "ferrite." Ferrite is iron powder
alloy that
is sintered (heated to not quite liquid state) and thus holds itself
together
without any polymer (plastic) binder.

Ferrite cores and structures will produce different results if broken
than the
manufacturer's data but cannot be predicted. In general, powdered
iron
cores already have their powder "broken" by suspension in the binder
and
can be glued/cemented together without undue change.

Ferrite things have been used in the microwave region for about 50
years
and, for uniformity/reproducibility, require the things to be unbroken
to achieve
the desired results. But, that is in the region of 1 GHz and above
and doesn't
apply to the typical IFT.

73, Len AF6AY

Thanks for the info!

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P