[ARC5] ARC 5 reciever backlash.

[John Hutchins]

Ken -

I agree, the best solution is to CLEAN first.
         " ........especially by dry, sticky lubricant and dirt that is 
70 years old", may also add SMOKE from pipes and cigarettes did not 
help.much either.

Clean then test and assess what is  wrong.

My 2 cents

On 4/23/2017 11:31 AM, Bill Cromwell wrote:
> Hi,
>
> Ken Gordon has good info and suggestions there. I can add some more to 
> those.
>
> The anti-backlash design incorporated into the gears is excellent and 
> similar designs are used in a lot of other gear. That can be overcome 
> by sloppy bearings and more especially by dry, sticky lubricant and 
> dirt that is 70 years old! I had one I had to remove from the radio 
> and disassemble to get it cleaned and lubed well enough. That radio 
> had been exposed to some 'extra' environmental stimulous.
>
> An option (if computers don't mortify you) is applying your audio out 
> from the receiver to the sound card in your computer running one of 
> the SDR packages. Your receiver will not be an SDR. There is no I and 
> Q quadrature output from your receiver. I will "mostly" work anyway. 
> You can have very narrow filtering (better than most "audio filter" 
> units. That wide chunk of spectrum coming through the radio will 
> actually be a good thing if you use the SDR software. You will tune 
> the range of the IF + audio bandwidth with the arrow keys on your 
> keyboard or with your mouse. The tuning rate will be substantially 
> improved without hacking your receiver to add 'bandspread'.
>
> You can also use DSP software like "Spectran" to get the narrow 
> filtering without modifying the receiver. But with straight DSP 
> packages you won't get the "bandspread" effect. You set up the DSP and 
> use the waterfall to identify where signals are and then use the 
> radio's tuning knob (fast tuning rate) to move the signal into the 
> filter area you have setup on the computer (I set mine at about 600 
> cps). You can also use the radio's tuning knob to move the signal in 
> the display to the onscreen cursor for detection (no bandspread 
> effect). That way you won't get gangrene or cooties from touching the 
> computer while tuning.
>
> The DSP package I use can narrow the audio passband to something less 
> than 100 Hz and the DSP can be narrower.  Some people would rather get 
> sick and die than use a computer or especially anything that says SDR. 
> But those approaches work. I get better results and I don't have to 
> hack the radio. The radio is doing all the heavy lifting. The computer 
> gives a big boost in performance and added capabilities. And the 
> computer is still not doing the radio operating - I am. I will not 
> have a radio that makes qso's for me and emails me a report to tell me 
> how much fun I am having and then updates my log on facebook!
>
> 73,
>
> Bill  KU8H
>
>
>
> On 04/23/2017 10:34 AM, J Mcvey via ARC5 wrote:
>> Trying to get everything in shape, but I'm getting frustrated with 
>> the ARC-5 receiver's touchy tuning.
>> 1) no selectivity
>> I am marginal at CW as it is, but when I have to hear two or three 
>> different tones at the same time it makes it nearly impossible for me.
>>
>> 2) backlash.
>> I haven't taken the receiver apart yet to look at the mech.
>> Any suggestions before I do?
>>
>>
>>
>>
>> ______________________________________________________________
>> ARC5 mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/arc5
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:ARC5 at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>