[ARC5] OT: Hally Instability.

[D C _Mac_ Macdonald]

I perceived my HQ-145 as quite stable.  I converted its original detector to Product Detector and added the very competent AGC circuitry from the National NCX-3.  Even the S-Meter worked on CW and SSB.  It and the HX-50 SSB rig displayed very little, if any, noticeable drift during operations including SSB traffic nets on 75m. 
  
* * * * * * * * * * * 
* 73 - Mac, K2GKK/5 * 
* (Since 30 Nov 53) * 
* k2gkk hotmail com * 
* Oklahoma City, OK * 
* USAF & FAA (Ret.) * 
* * * * * * * * * * * 
 

> From: wlfuqu00 at uky.edu
> To: arc5 at ix.netcom.com; pei7cn at eircom.net; arc5 at mailman.qth.net
> Date: Sat, 14 Nov 2015 16:34:24 +0000
> Subject: Re: [ARC5] OT: Hally Instability.
> 
>   Now, my SX101A was quite stable. It was my first real SSB hamband receiver.
> However, the SX100 I had was terrible and bad microphonics in the local oscillator.
> I think part of the problem was trying to jam to much into such a small package.
> After going to crystal controlled oscillators in first conversion things improved considerably.
>    I was surprised that my HQ110 was as good as it was. I could drop it a half inch and
> no microphonics. 
> 73
> Bill wa4lav
> 
> ________________________________________
> From: ARC5 [arc5-bounces at mailman.qth.net] on behalf of David Stinson [arc5 at ix.netcom.com]
> Sent: Saturday, November 14, 2015 10:26 AM
> To: Paddy Ryan; arc5 at mailman.qth.net
> Subject: [ARC5] OT: Hally Instability.
> 
> I'm not doubting anyone who says their Hallys were stable.
> I do know in 40+ years of hamming, I've handled dozens
> of them and never seen a single one from the "ham"
> market line that didn't show mechanical instablilty
> and "wibble-wobbles" above about 12 MC.
> Is it possible this was some sort of aging-related
> design flaw that a few were spared?
> Has anyone ever done a through investigation
> to find the root of it?  Coils mounted on a long
> bandswitch that will transmit shocks like a
> tuning fork always seemed a candidate to me.
> Most likely there are multiple causes.
> 
> 73 D.S.