From w2dgb at ptd.net  Thu Feb 15 17:04:00 2018
From: w2dgb at ptd.net (Bill W2DGB)
Date: Thu, 15 Feb 2018 17:04:00 -0500
Subject: [HBR] BC453 IF transformers in HBR11
In-Reply-To: <57E95713-E39C-4099-89AB-D5F96BFA01BB@comcast.net>
References: <1613372b455-171d-aa88d@webjas-vaa121.srv.aolmail.net>
	<57E95713-E39C-4099-89AB-D5F96BFA01BB@comcast.net>
Message-ID: <000601d3a6a8$e5e6c8a0$b1b459e0$@ptd.net>


Scott,

Just reread this from you and can offer some thoughts...

The usual way to wire a receiver is 1. The power supply, and then the audio.  2. Then go to the Ifs and so forth.

i.e....from the back towards the front, checking as you go.

Another thought:  I just learned the AWA Museum received a bunch of crystals from the Bliley Co when they got out of the business  (At least that is what I heard.)  If you need a crystal, you can contact Ed Gable at the museum...he just might have what you need.

73,  Bill   w2dgb



-----Original Message-----
From: hbr-bounces at mailman.qth.net [mailto:hbr-bounces at mailman.qth.net] On Behalf Of Whitebear1122
Sent: Friday, January 26, 2018 3:49 PM
To: ka9p at aol.com; HBR Receiver List <hbr at mailman.qth.net>
Subject: Re: [HBR] BC453 IF transformers in HBR11

Just my 2 cents.  I?ve resumed working on my HBR-13.. I know, it?s taking a long time.  I got held up with the IF?s as well.  After some trial and error I decided to move the center frequency from 85 KC to 100 KC.  I unsoldered the fixed caps in the can, replaced them with 120 PF silver mica?s, and they are now right around 100 KC.  I?ve converted 2 out of the 4 so far.  The first two are the input IF configurations.  The second stage will use the tapped 2nd IF, and the third stage will use the tapped 3rd IF.  

I have the RF front end and first two 1600 KC stages wired.  Starting on the 100 KC stages now, so I have not tested this out yet.  

I?m thinking that there will be plenty of gain with those regenerative IF stages that the tapped IF?s will be find.  If not, then I?ll change them out.

73, Scott WA9WFA


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From smithab11 at comcast.net  Thu Feb 15 20:52:37 2018
From: smithab11 at comcast.net (B. Smith)
Date: Thu, 15 Feb 2018 20:52:37 -0500
Subject: [HBR] BC453 IF transformers in HBR11
In-Reply-To: <000601d3a6a8$e5e6c8a0$b1b459e0$@ptd.net>
References: <1613372b455-171d-aa88d@webjas-vaa121.srv.aolmail.net>
	<57E95713-E39C-4099-89AB-D5F96BFA01BB@comcast.net>
	<000601d3a6a8$e5e6c8a0$b1b459e0$@ptd.net>
Message-ID: <a1c0ef37-e9c1-d5d1-b07c-22c648abb6f6@comcast.net>

 ?? When choosing IF coils and 2nd Osc crystals be sure and check your 
local listing to see what frequency the AM radio stations are on.
k4che
http://k4che.com/HBR/Testing/Progress%20Testing%20pg%201.htm


On 2/15/2018 5:04 PM, Bill W2DGB via HBR wrote:
> Scott,
>
> Just reread this from you and can offer some thoughts...
>
> The usual way to wire a receiver is 1. The power supply, and then the audio.  2. Then go to the Ifs and so forth.
>
> i.e....from the back towards the front, checking as you go.
>
> Another thought:  I just learned the AWA Museum received a bunch of crystals from the Bliley Co when they got out of the business  (At least that is what I heard.)  If you need a crystal, you can contact Ed Gable at the museum...he just might have what you need.
>
> 73,  Bill   w2dgb
>
>
>
> -----Original Message-----
> From: hbr-bounces at mailman.qth.net [mailto:hbr-bounces at mailman.qth.net] On Behalf Of Whitebear1122
> Sent: Friday, January 26, 2018 3:49 PM
> To: ka9p at aol.com; HBR Receiver List <hbr at mailman.qth.net>
> Subject: Re: [HBR] BC453 IF transformers in HBR11
>
> Just my 2 cents.  I?ve resumed working on my HBR-13.. I know, it?s taking a long time.  I got held up with the IF?s as well.  After some trial and error I decided to move the center frequency from 85 KC to 100 KC.  I unsoldered the fixed caps in the can, replaced them with 120 PF silver mica?s, and they are now right around 100 KC.  I?ve converted 2 out of the 4 so far.  The first two are the input IF configurations.  The second stage will use the tapped 2nd IF, and the third stage will use the tapped 3rd IF.
>
> I have the RF front end and first two 1600 KC stages wired.  Starting on the 100 KC stages now, so I have not tested this out yet.
>
> I?m thinking that there will be plenty of gain with those regenerative IF stages that the tapped IF?s will be find.  If not, then I?ll change them out.
>
> 73, Scott WA9WFA
>
>
> ______________________________________________________________
> HBR mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hbr
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:HBR at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
> ______________________________________________________________
> HBR mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hbr
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:HBR at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html



From whitebear1122 at comcast.net  Sat Feb 24 14:13:51 2018
From: whitebear1122 at comcast.net (Whitebear1122)
Date: Sat, 24 Feb 2018 13:13:51 -0600
Subject: [HBR] HBR Receiver BFO Question
References: <9F892050-7916-4FC9-942C-D9C47D986F02@comcast.net>
Message-ID: <1A977041-734C-4572-910E-020DC6C371CD@comcast.net>

Hi, I am working on the HBR-13 build.  Just finished the BFO and have powered it up separately.  I have a question regarding the output waveform of the oscillator.  While I scope out the grid side and get a nice sine wave, the output of the BFO is not symmetrical.  It?s on frequency, it sounds fine, but it?s not a sine wave anymore.   I tried submitting this post last week with a small photo but it never came through. I have a photo that I can email.  What is the BFO output wave shape supposed to look like?  Is it supposed to be a sine wave?  Thanks, 73, Scott WA9WFA


From waltah at earthlink.net  Sat Feb 24 15:31:02 2018
From: waltah at earthlink.net (Walt Hutchens)
Date: Sat, 24 Feb 2018 15:31:02 -0500
Subject: [HBR] HBR Receiver BFO Question
In-Reply-To: <1A977041-734C-4572-910E-020DC6C371CD@comcast.net>
References: <9F892050-7916-4FC9-942C-D9C47D986F02@comcast.net>
	<1A977041-734C-4572-910E-020DC6C371CD@comcast.net>
Message-ID: <229473726.20180224153102@earthlink.net>

Whitebear1122 said:

> What is the BFO output wave shape supposed to look like? Is it
> supposed to be a sine wave?

Probably not.

Most bfos -- most ham-purpose oscillators -- operate class C. The
current suppling the power -- plate current -- flows in pulses. Unless
the oscillator is designed so that current drives the tank circuit at
a capacitor -- a Colpitts circuit for example -- the VOLTAGE there and
often at some other places in the circuit will be a distorted
sine wave at best.

This isn't a problem for the BFO as such -- only its fundamental
matters to that function. However a non-sineusoidal voltage waveform
will increase the difficulty of eliminating BFO harmonics from the
front end of the receiver.

100 kcs BFO? Or 85 kcs? Far enough off that the problem should be
minor. Follow the HBR-13C design closely and I'd guess you should be
okay, though receiving SSB calls for more BFO output than was needed
for the original designs so the harmonic levels will be higher.

Just one footnote to that: Since the CURRENT is always a pulse (lots
of harmonics) if it flows in very much chassis it can be coupled to
other signals that flow in that chassis. As a rule of thumb return all
the grounds for an oscillator to the same lug, including bypasses,
etc.

Many words to say 'not a problem to worry about now.'

Walt Hutchens
ex-KJ4KV


From whitebear1122 at comcast.net  Sun Feb 18 20:45:05 2018
From: whitebear1122 at comcast.net (Whitebear1122)
Date: Mon, 19 Feb 2018 01:45:05 -0000
Subject: [HBR] Question about HBR BFO Waveform
Message-ID: <9F29004E-27A0-4D9D-9457-5312A45CB546@comcast.net>

I finished wiring the BFO today and powered it up.  Tunes up nicely at 100 KC, sounds fine on a receiver.  The output waveform is not what I expected though.  I was expecting a sine wave but instead get something different.  Is the Hartley BFO output supposed to be a clean sine wave?  I have a picture of the waveform that I can email  if you can help analyze it. 

In lieu of information I?m going to wire up the BFO circuit on a piece of perf board to see if I get the same results.  My HBR BFO is tightly crammed in the little cabinet so maybe I did something wrong.  The perf board version may yield something different.

I don?t think the reflector allows pictures but I will include the waveform here just in case.  

Thanks, 73, Scott WA9WFA

