[CQ-Contest] 419 band pass filters..... can a heverivier dutycoilbe installed ??

[Jukka Klemola]

The error is current.
Use multiple smaller parallel capacitors .. or use better caps.

World does develop.
There are better capacitors available than the brown silver-micas.
Yep - they were the state of the art in 1900's.

Hi.
Could not resist writing that in a Friday manner.

Keep on having FUN !


Tuning the ICE 10m filters takes either tweaking the lead lengths or
coils.
Maybe selecting caps of few pF up/down will help, too.
10m filters are not very easy to tune.


I have beefed up my 40m ICE that was fried by OI2HQ team a few years
back .. Brits fried it. I replaced the toroids with air wound coils.
The re-furbished filter is better than new!
80-160m filters' toroid coils cannot be replaced by air-wounds.


73,
Jukka OH6Li


...
>My 419A's are rated at 200 watts.
>
>During a DXpedition to VP8 (Falklands), the 10M section acted up (VSWR
went
>to 5) when a tuner was placed between it and a vertical antenna with
high
>VSWR.  At the time I thought the unit might be bad so swapped it with
>another 419A from the second radio running a different band.  After a
short
>period of time it too went to high VSWR.  Later, back at home, I
contacted
>ICE and they sent replacement caps for the 10M section for both units.
>
>I decided to beef up the 10M section in one of the units by doubling
the >cap voltage ratings through use of multiple caps.  This did not
work.  I >could not get the bandpass frequency to adjust properly for
10M.
...
>
>73, Keith NM5G