[Hammarlund] HQ-129-X Question

[Carl]

----- Original Message ----- 
From: "Kenneth G. Gordon" <kgordon2006 at frontier.com>
To: "Richard Knoppow" <1oldlens1 at ix.netcom.com>; 
<hammarlund at mailman.qth.net>; "Bob Macklin" <macklinbob at msn.com>
Sent: Monday, November 29, 2010 5:34 PM
Subject: Re: [Hammarlund] HQ-129-X Question


> On 29 Nov 2010 at 14:03, Bob Macklin wrote:
>
>> Part of the problem is you do not know how accurate the dial was when
>> the receiver was new.
>
> True.

Disagree. The dials were always accurate especially at the end points. The 
ones I have here all have very little run out in between. This covers the 
120X and later models, the tuning gangs and dials are the same thru the 140X 
I believe..

>
>> And in 1960 about the only company that had a really linear LO was
>> Collins
>
> Agreed, although some got very close, like the ARC-5s.

Disagree again, Central Electronics was as good or better than Collins. 
There were also several others building PTO's for the R-390/390A going well 
back into the 50's.

>
>> With the standard GC receivers of the period all you could do was
>> adjust the inductor at the low end of the band and the trimmer
>> capacitor at the high end.
>
> Yes, mostly, although in some receivers, you were sometimes instructed to
> bend the outer plates to "tweak" their tuning in between end points, and
> those capacitors were designed for that purpose. I think the HRO may have
> been one of those. I KNOW the ARC-5s were.


The HRO had the half turn loop, you never touched the plates except to 
lightly move them to see which way the alignment was needed; they were too 
heavy to take a set and went right back.


>
>> Before 1960 we did not have digital
>> counters. And the ones I do remember from about 1960 would not work at
>> HF frequencies.
>
> Again, true, although there were shortly made available "down counters" 
> or
> "dividers" you could add ahead of the basic counter to extend the range.

National had HP and Beckman counters around that time. Rows of nixie tubes 
and converters to 100 mc.They had the synthesized, digital readout WRR-2 and 
FRR-59 to deal with.

>
>> Instead we used frequency meters like BC-221s.
>
> Which are STILL very useful. I have two and use them for receiver 
> alignment
> by setting one at the top end and the other at the low end of each band I 
> am
> aligning. The '221 is very stable and very accurate, especially for its 
> early
> design.


I use a pair of HP-606A's for that with a take off for digital counters. It 
really makes alignment easy. I paid $90 total for both HP's. I like them 
better than a HP 8640B for HF and lower receiver work
Didnt like the BC-221 even in the Navy. Have one and a LM-21 here just for 
display, never turned them on.


>> These LOs will never have the precision of today's rigs. And they
>> don't need it.
>
> Again, true, but in Richard's case, it DOES sound to me as though it is 
> not
> even within the specifications of the time.

Not even close.

>
> So, we would like to get the problem fixed, and perhaps learn something in
> the process.

Yep

Carl
KM1H


>
> Ken Gordon W7EKB
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