Hallicrafters Alignment Pages

If your radio doesn't pick up at least one station, you should go to the CPR page. You are not ready for this.

As of 23 June 2026, this entire alignment procedure is under development. Please explore and comment but don't get upset if you run across something stupid or just plain wrong. There are quite a few missing pages that do not need reporting.

This is the top-level page for everything alignment related.
The pages are in multiple levels and categorized by functional blocks:

  1. Measure - A procedure or page to determine a value
  2. Test - A procedure or page to verify that something is working correctly
  3. Adjust - A procedure or page check an operation and what to do if it isn't right
  4. Theory - Notes on how it is supposed to work

The sections below are listed in the order of complexity. Simplest first.

Early Radios (SX-28)

Measure Crystal Frequency

The crystal is supposed to resonate at 455 KHz but like all components, it varies.
Knowing the actual resonate frequency of your crystal is important as it will be used in later steps.
Acceptable limit not determined yet.

   Measure

BFO

The BFO is independant of everything except power.

   Adjust    Theory

Local Oscillator

The only input to the oscillator are the tuning capacitors and the band switch position but it's output is key to everything else.

The cgi version asks for the crystal frequency determined above and adjusts all the expected values for the different bands accordingly. The assumption is that the IF chain will be adjusted to the same frequency as the crystal. If the crystal is way off frequency, this isn't going to work.

The non-cgi version assumes that the IF chain will be aligned to 455 KHz no matter what the crystal is.

   Adjust    Adjust (cgi version)    Theory

1st RF

There are no knobs to twiddle in the 1st RF section.

   Theory

2nd RF

   Adjust    Theory

Mixer

   Adjust    Theory

IF

   Adjust    Theory

Late Radios (SX-28A)

This section won't be started until the early radio section above is working. There's a lot of cut-n-paste and hopefully, it only gets done once.


Page: /Alignment/Alignment_root.shtml

Last modified: Tuesday, 23 Jun 2026