On Tue, 10 Feb 2009, wrote:

On Feb 9, 9:14*pm, " wrote:
Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? *TNX 73 *Harold
Followup: I am looking for a 3395 KHZ. AM Filter for a Heathkit SB301.
The AM filter was offered as an Option . The SB 301 will not receive AM
without the optional filter....It has AM detector and everything but the
filter..I thought someone might have worked out a substitute for the
Heath filter..like a high Q tuned IF can or whatever... TNX Harold


At 3395KHz, LC circuits won't provide enough selectivity. You're either
going to have to find a Heathkit filter for sale, which likely is
going to be hard since the SB line was primarily for SSB so the
optional AM filters would be in scarce supply to begin with, or see
if you can get a more recently manufactured filter, assuming those
third party companies have bothered with AM bandwidth filters.

You could have some crystals ground to the frequency, and try making
a ladder filter. Or get just one, and make one of those old phasing
type crystal filters, which would need loading to get the needed
wide bandwidth, and of course wouldn't provide good skirt selectivity.

You do realize you could do what people did at the time, when SSB-only
rigs starting coming along but AM was still common? Receive using
the SSB receiver, which will chop out the unneeded sideband and
knock the carrier down so it won't be a bother, and then the signal
becomes SSB inside the receiver where the BFO can properly demodulate
it.

Michael VE2BVW

wrote in message
...
On Feb 9, 9:14 pm, " wrote:
Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? TNX 73 Harold Followup: I am looking for a 3395 KHZ.
AM Filter for a Heathkit SB301 .The AM filter was offered as an Option .
The SB 301 will not receive AM without the optional filter....It has AM
detector and everything but the filter..I thought someone might have
worked out a substitute for the Heath filter..like a high Q tuned IF can
or whatever... TNX Harold

I worked on a National NC-300 a few months ago. It had a conversion from a
coil to a crystal at the second converter stage.
About half way down the page: http://www.ppinyot.com/N/national/national.htm
look for the "Second Converter modification at V3 6BE6" paragraph.
Schematics and FNBs are on BAMA.

The crystal used in the NC-300 is not at your frequency. But a crystal
company should be able to make you one. I purchased Hammarlund specific
crystals from http://www.icmfg.com/ The crystals were about 25 bucks each.

AND the woman that answered the phone is not just a receptionist. She knew
exactly which crystals I needed for the Hammarlund and what overtone and
impedance!!! Not that she is a woman but she knew exactly what the vintage
crystal replacement I needed!

I hope this leads you some where.

Paul P.

On Wed, 11 Feb 2009, Paul P wrote:


wrote in message
...
On Feb 9, 9:14 pm, " wrote:
Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? TNX 73 Harold Followup: I am looking for a 3395 KHZ.
AM Filter for a Heathkit SB301 .The AM filter was offered as an Option .
The SB 301 will not receive AM without the optional filter....It has AM
detector and everything but the filter..I thought someone might have worked
out a substitute for the Heath filter..like a high Q tuned IF can or
whatever... TNX Harold

I worked on a National NC-300 a few months ago. It had a conversion from a
coil to a crystal at the second converter stage.
About half way down the page: http://www.ppinyot.com/N/national/national.htm
look for the "Second Converter modification at V3 6BE6" paragraph. Schematics
and FNBs are on BAMA.

The crystal used in the NC-300 is not at your frequency. But a crystal
company should be able to make you one. I purchased Hammarlund specific
crystals from http://www.icmfg.com/ The crystals were about 25 bucks each.

AND the woman that answered the phone is not just a receptionist. She knew
exactly which crystals I needed for the Hammarlund and what overtone and
impedance!!! Not that she is a woman but she knew exactly what the vintage
crystal replacement I needed!

Who knows, but likely they have it on computer.

The old crystal manufacturers tended to keep such information around, and
certainly once they had the information because someone had sent it to
them to get a needed crystal ground, they'd surely have kept it. So
after a while, they could just look up the information. If they bothered
to computerize it, then all they'd have to do is type in some search
terms, and out would pop the needed information. That wouldn't require
someone who knew all the details by heart.

Michael VE2BVW

On Tue, 10 Feb 2009 22:47:06 -0500, Michael Black wrote:

On Wed, 11 Feb 2009, Paul P wrote:


wrote in message
news:722c01b0-
...
On Feb 9, 9:14 pm, " wrote:
Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? TNX 73 Harold Followup: I am looking for a 3395
KHZ. AM Filter for a Heathkit SB301 .The AM filter was offered as an
Option . The SB 301 will not receive AM without the optional
filter....It has AM detector and everything but the filter..I thought
someone might have worked out a substitute for the Heath filter..like
a high Q tuned IF can or whatever... TNX Harold

I worked on a National NC-300 a few months ago. It had a conversion
from a coil to a crystal at the second converter stage. About half way
down the page: http://www.ppinyot.com/N/national/national.htm look for
the "Second Converter modification at V3 6BE6" paragraph. Schematics
and FNBs are on BAMA.

The crystal used in the NC-300 is not at your frequency. But a crystal
company should be able to make you one. I purchased Hammarlund
specific crystals from http://www.icmfg.com/ The crystals were about
25 bucks each.

AND the woman that answered the phone is not just a receptionist. She
knew exactly which crystals I needed for the Hammarlund and what
overtone and impedance!!! Not that she is a woman but she knew exactly
what the vintage crystal replacement I needed!

Who knows, but likely they have it on computer.

The old crystal manufacturers tended to keep such information around,
and certainly once they had the information because someone had sent it
to them to get a needed crystal ground, they'd surely have kept it. So
after a while, they could just look up the information. If they
bothered to computerize it, then all they'd have to do is type in some
search terms, and out would pop the needed information. That wouldn't
require someone who knew all the details by heart.

Michael VE2BVW

But, in such a situation having someone willing and able to properly
fondle the keyboard, then cheerfully tell you what you need to know, is
still better than a snide gum-chewing receptionist!

I try not to undervalue order-takers and such. Given how much value they
can add when they're on the ball (and how much they can screw up when
they're not), one cannot dismiss them as "just" anything.

--
http://www.wescottdesign.com

Tim Wescott wrote:

But, in such a situation having someone willing and able to properly
fondle the keyboard, then cheerfully tell you what you need to know, is
still better than a snide gum-chewing receptionist!

I try not to undervalue order-takers and such. Given how much value they
can add when they're on the ball (and how much they can screw up when
they're not), one cannot dismiss them as "just" anything.

Well, we 'hams' often are not the easiest customers to deal with because
we 'know' more than the gal on the other end of the phone That said,
I not so long ago ordered some xtals from JAN and mentioned my old
Harvey-Wells TBS-50 and the gal lit up like she knew what I was talking
about.

JAN has my business ever since.

-Bill

In article ,
Bill M wrote:
Tim Wescott wrote:

But, in such a situation having someone willing and able to properly
fondle the keyboard, then cheerfully tell you what you need to know, is
still better than a snide gum-chewing receptionist!

I try not to undervalue order-takers and such. Given how much value they
can add when they're on the ball (and how much they can screw up when
they're not), one cannot dismiss them as "just" anything.

Well, we 'hams' often are not the easiest customers to deal with because
we 'know' more than the gal on the other end of the phone That said,
I not so long ago ordered some xtals from JAN and mentioned my old
Harvey-Wells TBS-50 and the gal lit up like she knew what I was talking
about.

JAN has my business ever since.

ICM and JAN are both this way and they are both absolute joys to deal with.
They know what you want, they know how to make it, and they know what a
fair price is.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

wrote:
Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? TNX 73 Harold

For crystals, try MH Electronics, Rancho Cucamonga, CA. Been using them
on MIL rigs, many with some pretty high currents. So far, 100%. They
say they use large blank crystals for their HC-6-style units, not those
sub-minis that will fail if you look at them crooked.
73 de K3HVG



--
Posted Via Newsfeeds.com Premium Usenet Newsgroup Service
----------------------------------------------------------
http://www.Newsfeeds.com

"Scott Dorsey" wrote in message
...
ICM and JAN are both this way and they are both absolute joys to deal
with.
They know what you want, they know how to make it, and they know what a
fair price is.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Jan, ICM, and Sentry... I must have spend hundreds of bucks
when I was a young ham on FM crystals for the latest Motorola
or RCA twoway castoff I was converting for one of the VHF or
UHF ham bands! I remember when ICM had cheap EX grade
crystals for experimenters, and when JAN would mail you
list of cheap surplus crystals they had on hand.

Pete

On Feb 9, 10:14*pm, " wrote:
Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? *TNX 73 *Harold

Heathkit AM filters show up on eBay and at hamfests from time to time.

There are two types, big and little. They work in different radio's.
The big filters are from the first SB radios. SB-300 used the big
filter, the SB-301 and SB-303 used the small filter.

Within the types, there are two bandwidths available. 3.5 kHz and 5.0
kHz.

The 3.5 was the optional filter for the SB ham band receivers like the
SB-300, SB-301 and SB-303.

The 5.0 was the STANDARD filter for the SB SWL receiver like the
SB-310 and the SB-313.

Expect to pay about $30 for a 3.5 and $100 for a 5.0 filter. The 3.5
is not "full frequency" and the 5.0 is more hi-fi.

You can force fit either filter type in any SB receiver but look for
the proper size and it will bolt in.

good luck.

In article
,
" wrote:

Looking to buy a 3395 AM filter as used in early tube Heathkit
receivers..any other suggestions on receiving AM with homebuilt filter
system? TNX 73 Harold

Harold-

There was a thread a few weeks ago, about someone buying out Heath's
remaining parts and manuals. I understand the company is still in
business, just not selling kits. http://www.heathkit.com/ If you
give them a call, they might tell you how to contact the person or
company that bought their old parts. There may be a slim chance your
filter is available.

Fred
K4DII