[R-390] Off switch Doesn't

[Jim Brannigan]

Thanks for all the replies, while I was reading them the switch "got better" 
(I just love these self-healing electronics)

Still, having a spare switch around is a prudent thing to do.

73,
Jim

> The standard fix when I was in the Army was to replace them.  Not hard, 
> though the down-time waiting for a replacement was a while.  Often long 
> enough we would just go ahead and disassemble the micro switch and burnish 
> the contacts.  After they were pulled mostly from the field and used for 
> training purposes, we just took a rubber mallet and gave the front panel a 
> whack where the micro switch was.  It invariably fixed it.  Never had to 
> do the same receiver twice.
>
> Les Locklear wrote:
>> NOS switches are available from Dan (Hank) Arney. Contact him at: 
>> hankarn at pacbell.net
>>
>> Les Locklear
>> Gulfport, Ms.
>> Dx'ing since '57
>> http://www.hammarlund.info/
>>
>> ----- Original Message ----- From: "Jim Brannigan" 
>> <jbrannig at optonline.net>
>> To: "Barry" <n4buq at knology.net>; <r-390 at mailman.qth.net>
>> Sent: Thursday, November 06, 2008 8:32 AM
>> Subject: Re: [R-390] Off switch Doesn't
>>
>>
>>> Thanks for all the input on the switch.  Does anyone have a part number?
>>> Are the micro switches available from Mouser or other sources?
>>>
>>> Tnx
>>> Jim
>>>
>>>
>>>>>>> I understand the AC micro switch is a common failure point.
>>>>>>> The micro switch in my 67 EAC is welded in the ON position.
>>>>>>> Is there a replacement/fix for this problem?
>>>>>>
>>>>>> Sometimes you can "work" the switch actuator a bit with a small
>>>>>> instrument and sometimes it will free itself.  I fixed one that way 
>>>>>> one
>>>>>> time.
>>>>>
>>>>> This is never a permanent fix, and rarely anything but a very 
>>>>> short-term
>>>>> one.  If the switch has welded itself once, it will do so again.  Even
>>>>> taking the switch apart and dressing the contacts is only a short-term
>>>>> fix.
>>>>>
>>>>> Microswitches are cheap -- buy a new one and install it.  Get the 
>>>>> highest
>>>>> contact current rating you can in the correct form factor.  While 
>>>>> you're
>>>>> at it, buy two, so you'll have one for next time.  Put a proper 
>>>>> snubber
>>>>> across the new switch to maximize its life.
>>>>>
>>>>> Best regards,
>>>>>
>>>>> Don
>>>>
>>>> I think in my case, it was just excess grease that had gotten down 
>>>> around
>>>> the plunger and was keeping it from popping fully back up.  Working it 
>>>> a
>>>> few times freed it up and it worked fine for years.  Yeah, welded,
>>>> corroded contacts, etc., are a different problem.
>>>>
>>>> Regards,
>>>>
>>>> Barry