[Hammarlund] SP-600

Wed Apr 13 10:31:14 EDT 2022

    I have see exactly one VLF receiver. It was for sale at the 
old C&H many years ago. I don't remember the style of the knobs 
or other details.
     The SP-600 had an odd antenna connector for balanced coax. 
Evidently this stuff was used for antenna feeders in commercial 
stations. Later the connector was changed to a UHF type. Changed 
at least one myself.
     I thought there was a handbook for the thing on the web 
somewhere but I don't seem to have it in my SP-600 folder so 
maybe not.
     Perhaps the BNC is for an external IFO.
    It is a very elaborate VLF receiver and covers a wider band 
than most of the military ones.
    Also has a somewhat different chassis arrangement.

On 4/13/2022 7:20 AM, Les Locklear wrote:
> Later variants of the SP-600 used a miniature tube in the Xtal frequency control. Another oddity, the original VLF's had a vertical plate with the SO-239 on it, the screw holes are on the chassis alongside the 6AL5. It would be interesting to see the underside of the chassis and see some dates on the bathtub capacitors.
> 
> Les
> 
> 
> ----- Original Message -----
> From: Loren Burkett <lcbur at sbcglobal.net>
> To: Thomas Hoyer <thoyer1 at verizon.net>
> Cc: <leslocklear at hotmail.com>, <Hammarlund at mailman.qth.net>
> Sent: 4/13/2022 8:51:53 AM
> Subject: Re: [Hammarlund] SP-600
> ________________________________________________________________________________
> 
> 
> Tom,  Les and I noted the same things you mentioned.  The aux crystal unit is a different design and the tube socket on it is not the octal.  It is so clean I would love to inspect it in person.  Sam said he would hold for pickup for me but I will not be bidding.
> Loren
> 
>> On Apr 13, 2022, at 8:34 AM, Thomas Hoyer via Hammarlund <hammarlund at mailman.qth.net> wrote:
>>
>> Interesting. Always wanted to find a "VLF" to add to the collection, but a little pricey for me.
>> BNC and mini toggle look to be add ons to me. BNC is not wired and the toggle looks like it controls the dial lighting. Someone added an SO-239 connector. No xtals or tube in the aux xtal unit.
>> Looks to be in good condition - I need to think about this one.........
>> TomW3TA
>>
>>
>> -----Original Message-----
>> From: Loren Burkett <lcbur at sbcglobal.net>
>> To: Les Locklear <leslocklear at hotmail.com>
>> Cc: Hammarlund at mailman.qth.net <Hammarlund at mailman.qth.net>
>> Sent: Wed, Apr 13, 2022 7:24 am
>> Subject: Re: [Hammarlund] SP-600
>>
>> Les,
>> This radio has many mysteries.  The tuning/band change knobs made me think of the 21A.  The dial faces seem unusually white. Note the non standard toggle switch near the meter.  The BNC connector seems to be from the factory as it is connected by the panel paint.  Many screw heads seem non standard.  Yes the tuning lock is missing but it could be replaced from a "parts" SP-600.  Is the meter face non standard?  Why would the nomenclature tag be wiped or never filled out?
>> This mystery radio seems to be a very late "one off" of some type,
>> Loren Burkett
>>
>>> On Apr 12, 2022, at 6:55 PM, Les Locklear <leslocklear at hotmail.com> wrote:
>>>
>>> There are too many things wrong that I can see. Wrong tuning and band change knobs, they are Dakaware style knobs like the Collins 51J/R-388 series. The tuning lock knob is missing, possibly the locking mechanism behind it. A bnc connector on the RH top front panel that goes where? And the nomenclature tag on top of the tuning condenser cover seems to have been scuffed up and is unreadable. The IEC type computer power cord isn't original...etc. Ya pays your money and ya takes your chances.
>>>
>>> Les Locklear
>>>
>>>
>>> ----- Original Message -----
>>> From: Kenneth G. Gordon <kgordon2006 at frontier.com>
>>> To: Loren Burkett <lcbur at sbcglobal.net>
>>> Cc: <Hammarlund at mailman.qth.net>
>>> Sent: 4/12/2022 6:42:29 PM
>>> Subject: Re: [Hammarlund] SP-600
>>> ________________________________________________________________________________
>>>
>>>
>>> On 12 Apr 2022 at 18:10, Loren Burkett wrote:
>>>
>>>> It is a typical eBay bidding.  About $900 now.  Look it up as it is in amazing condition.
>>>
>>> Thanks, Loren. I did check it out. It is in good condition, but it is missing the cover for it.
>>> There is supposed to be a complete cover for it, made out of steel.
>>>
>>> Ken W7EKB
>>> ______________________________________________________________
>>> Hammarlund mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/hammarlund
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:Hammarlund at mailman.qth.net
>>>
>>> List Administrator: Gary Harmon, K5JWK
>>> ** For Assistance: gharmon at idworld.net **
>>>
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>> ______________________________________________________________
>>> Hammarlund mailing list
>>> Home: http://mailman.qth.net/mailman/listinfo/hammarlund
>>> Help: http://mailman.qth.net/mmfaq.htm
>>> Post: mailto:Hammarlund at mailman.qth.net
>>>
>>> List Administrator: Gary Harmon, K5JWK
>>> ** For Assistance: gharmon at idworld.net **
>>>
>>>
>>> This list hosted by: http://www.qsl.net
>>> Please help support this email list: http://www.qsl.net/donate.html
>>
>> ______________________________________________________________
>> Hammarlund mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/hammarlund
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Hammarlund at mailman.qth.net
>>
>> List Administrator: Gary Harmon, K5JWK
>> ** For Assistance: gharmon at idworld.net **
>>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> ______________________________________________________________
>> Hammarlund mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/hammarlund
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Hammarlund at mailman.qth.net
>>
>> List Administrator: Gary Harmon, K5JWK
>> ** For Assistance: gharmon at idworld.net **
>>
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> Hammarlund mailing list
> Home: http://mailman.qth.net/mailman/listinfo/hammarlund
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Hammarlund at mailman.qth.net
> 
> List Administrator: Gary Harmon, K5JWK
> ** For Assistance: gharmon at idworld.net **
> 
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

-- 
Richard Knoppow
1oldlens1 at ix.netcom.com
WB6KBL