[Drake] Several Drake questions

[Larry Taft]

MORE!

For the audio amp stuff I recommend the Sherwood mod along with his 
power supply redo as those changes make the R-4C into a cool cool box.  
Also the mixer and the product detector kits reduce the internal noise.  
The expensive filters are your call, CW contesters swear by them.
I've installed several of the kits in customers R-4Cs and they work good.

The really modern mod is to get a Softrock 40 type module and run the IF 
into a good sound card in your PC and use the several programs for the 
SDR receivers.  Beats anything you can buy. ANYTHING!  The closer to the 
front end you can go with the Softrock the better it works.

 Obviously I am a real Drake fan and have many pieces in the shack (some 
actually work) but the SDR stuff is a real improvement to the art of 
receiver design.  My next experiment is to get a Softrock running at 48 
MHz and tap into the high IF of a R-7 receiver that has seen better days.
This should give me an all band setup with the SDR performance.

73, Larry  K2LT
drakerepair.com   800-687-9161

Larry Taft wrote:
> For the reduction drive try Oren Elliott Products.  They also make old 
> time variable caps as used in the L-4 and L-7 amps.
>
> www.orenelliottproducts.com
>
> 73, Larry  K2LT
> drakerepair.com
>
> Dave Maples wrote:
>> All: I have acquired a Drake C line that I'm quite happy with.  I 
>> have some
>> questions, though, about it and the B line that I also have.
>>
>> 1. I'm wondering if there's anyone who knows where the reduction 
>> drives used
>> on the preselector tuning could be obtained.  The Jackson Bros. 6:1
>> reduction drive seems to be the closest thing, but I doubt that 
>> that's what
>> is being used.  Anyone have a clue here?
>>
>> 2. Anyone have a preferred source for band crystals for the Drakes?  
>> I've
>> got a bum 40M crystal in the R4C (about 15 kHz off, if you can believe
>> that).
>>
>> 3. I have recently used a Velleman K4001 audio amplifier in a 
>> work-related
>> project.  This amp delivers 7 watts max to a 4-ohm load (with a 15 VDC
>> supply).  It's based on the TDA2003 integrated circuit and will 
>> operate from
>> a supply of 8-18 VDC.  It draws 500 MA at 7 watts out.  It has about 
>> 40 dB
>> of gain.  Any reason why I couldn't use this to replace the single
>> transistor special in the R4C?  I've read about the LM380 
>> replacement; this
>> seems like an even cleaner approach.  I believe I'll have to replace the
>> regulators as well, if I read correctly.  Any thoughts on this approach?
>>
>> All comments welcome!
>>
>> Thanks,
>> Dave WB4FUR
>>
>>   
>
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