[Heathkit] SB-301

Mon Feb 18 21:35:35 EST 2013

Bill,

I agree with your sentiments.  

I have two unmodified Heathkit RX-1 receivers, one is paired with a HX-10 "Marauder" and HA-10 amplifier and the other is paired with a TX-1, SB-10, and KL-1 "Chippewa" amp.  I went through both receivers, replaced a few bad/out of spec components, cleaned up some workmanship, and then carefully aligned them.  Both Mohawks work very well on all modes.  One key is not to run the IF gain anywhere close to maxium.  A lot of the receivers of this era had an internal gain set control that was to be adjusted during alignment, Heathkit put this on the front panel in the form of the IF gain control in order to give the owner the ability to fine tune the receiver for varying conditions.  Unfortunately a lot of owners run this control wide open which turns the RX-1 into a noisy and distortion prone receiver.  For newer users getting used to this receiver tuning on AM should be done with the BFO on and set for center and then tune for zero beat.  Now switch to AM mode and you can switch sidebands as needed to avoid interference either above or below your operating frequency.  This same method is useful for the Hallicrafters SX-96 and later family which uses the same electronic sideband switching via the final mixer.

The HQ-170 and HQ-180 are two of my favorite all mode receivers.  When I first got my Johnson Ranger/Desk KW setup I paired it with a National HR0-50 like the Johnson advertisement.  When I started acting as net control for the Midwest Classic Radio Net (AM net on 3885) I quickly realized I needed something that provided selectable sideband on AM to pull some of the weaker check-ins out of the QRM and started using a HQ-170A which worked wonderfully.  A few years ago I finally got a Hallicrafters SX-88 which is a receiver I have wanted since I came across an old advertisement for one while studying for my novice ticket in 1974.  This is the receiver I now use with the Ranger/Desk Kilowatt station and it does a great job but I sometimes miss the easy switch selectable sideband for AM offered by the HQ-170.  The high Q transformers in the SX-88 low IF allow choice of either sideband on AM but you have to reset the band spread tuning to select the desired sideband since the SX-88 doesn't have the dual crystal mixer setup of the SX-96 and later SX-88 descendants.  The HQ-170/180 are two of the most versatile all mode receivers available.  You can add this capability to many receivers using the Hammarlund HC-10 SSB adapter which basically adds the final mixer, 60 Khz. low IF, AGC, slot filter, noise limiter, detector, and audio output circuitry from the HQ-170/180 to any receiver with a 455 Khz. IF.

The SB-301 with all of its filters does a fine job and unlike the Collins S line it doesn't have those annoying 200 Khz. wide bands.  It is a real pain sometimes with the S Line when you need to go from the top of one segment to the low end of the next highest segment.  In that regard I really like how Drake set up the VFO in their MSR-2 and DSR-2 receivers.  It consists of two mechanically coupled VFO units each covering 100 Khz. and offset 180 degrees so as you tune past the top of the 100 Khz. segment the other VFO is electronically switched in and you are immediately at the bottom of the segment allowing you to very quickly and easily tune anywhere within the range.

The only way to really evaluate whether a receiver is right for you is to get a good hands-on test of one that is in proper working order.  Opinions are useful in indicating things you might want to check or question but these opinions should simply be an input to your own well reasoned and hopefully fact based decision.

Rodger WQ9E

-------- Original Message --------
> From: "W. Harris" <nbcblue at hotmail.com>
> Sent: Monday, February 18, 2013 7:45 PM
> To: Heathkit Reflector <heathkit at mailman.qth.net>
> Subject: Re: [Heathkit] SB-301
> 
Deleted long list of receivers...
> 
> Everyone is entitled to their own opinion, even if it is wrong. 
> 
> Bill - K5MIL
> 
>  		 	   		  
> ______________________________________________________________
> Heathkit mailing list
> Home: http://mailman.qth.net/mailman/listinfo/heathkit
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Heathkit at mailman.qth.net
> 
> List Administrator: Duane Fischer, W8DBF
> ** For Assistance: dfischer at usol.com **
> 
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html 