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THE AM BULLETIN BOARD => Technical Forum => Topic started by: WA1HZK on August 19, 2005, 07:38:55 PM



Title: Drake R4A
Post by: WA1HZK on August 19, 2005, 07:38:55 PM
I have a working Drake R4A Rcvr. I'm looking for opinions on using this thing on AM? I bought it on E-Bay last year for around 50 bucks & just got around to plugging it in tonight and it actually works! Doesn't work on AM but copies Slop Bucket just fine. So Whadda ya know about this one? I'm trying to set up a future AM'er.

PS
Still looking for the Mods for the SX-101A that's on the floor waiting for the details.
Keith
WA1HZK


Title: Re: Drake R4A
Post by: Vinnie/N2TAI on August 19, 2005, 10:55:45 PM
Been using a R4 with my DX100 for 3 or 4 years now. Just put the selector switch on AM and set the Passband for 4.3. The R4 predates the R4A. Set works fine, had to clean the switches when I got it, used Caig Deoxit.


Title: Re: Drake R4A
Post by: wn5t on August 20, 2005, 12:02:28 AM
The R4A has similar specs to my R4B.  4.8 kHz at -6dB and 20 kHz at -60 dB.   That's not a  poodle skirt...it's almost an "Oh, Rhett!" full skirt...9 MHz, it's not...but it's a good rx.  Anywho, I've compared my R4B to my IC-746 (15K or 9K on AM)  and my SX-110.  The MS-4 speaker leaves something to be desired.  Even with my eq'd audio system, the IC-746 is a wider rx and sounds better.  However, sensitivity-wise, the R4B is every bit the 746's equal...if not it's better (my R4B came in somewhere around -133 dBm).  For listening to broadcast quality stations, it's okay.  I miss the low's mostly.  That said, I like listening to the morning 3885 bunch on it.   It  sounds better than the SX-110.  Oh...and it has that external mute line.  One thing that I have done to help it out is that I have an automotive stereo EQ in-line going to the small stereo amp.  With the R4B I have to add all the bass possible, whereas with the '746 I have to cut some off the bottom. 

That lucky future AM'er won't fully appreciate the East Coast big guns.  They will be heard and they'll sound nice...just not as nice as they really are.  I do recommend the EQ ( the cheap one from JC Whitney) and the stereo amp.  Mine is the little RCA model from Rat Shack, but any stereo amp will work. (I've had less RFI with the stereos than with a computer spkr amp.)    If you like, I can make an mp3 and send it your way.

Easy to set up.  Easy to use.  Good rx.  You wrote that this one doesn't work on AM.  The Drakelist ( www.zerobeat.net/drakelist (http://www.zerobeat.net/drakelist) ) is a great place for troubleshooting help.   Ditto on the DeOxit.

I hope you're friend enjoys the rx.   


Title: Re: Drake R4A
Post by: Vinnie/N2TAI on August 20, 2005, 09:24:27 AM
Yea don't use a computer speaker system. their amplifiers are junk and don't have the proper bypassing so they make excellent radio receivers.
Hit a few garage sales and you can come up with some really nice name brand, Dynaco, Fisher, Murantz, etc. stereo equipment
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands