eHam

eHam Forums => Boat Anchors => Topic started by: N3DT on January 12, 2013, 05:30:30 PM



Title: Any market for R390A/URR?
Post by: N3DT on January 12, 2013, 05:30:30 PM
I have a couple of them.  They work, but need some detailing, which I am doing, but wonder if there is any market for these BAs any more?  I've replaced the caps and tubes, but I don't figure it's worth much more than that.  I really have no use for them except to play with them.  I've gotten the mechanical dial pretty smooth now.

They're fun to play with, but not much use. really.  I've seen the SDR for the IF, but that doesn't do much for me either.

If anyone knows where to get little parts cheap, I'd be interested, like the top panels, little parts like the inter-board connectors.  They're not in bad shape, just some of the typical gov't mods.  The meters actually work on one of them.


Title: RE: Any market for R390A/URR?
Post by: KE5YTV on January 13, 2013, 02:58:40 AM
I have just finished my first one. I enjoyed the project and will probably buy another.  ;D

Mike
KE5YTV


Title: RE: Any market for R390A/URR?
Post by: KD8IIC on January 13, 2013, 03:12:57 PM
Fair Radio in Lima Ohio has some parts.


Title: RE: Any market for R390A/URR?
Post by: K1ZJH on January 13, 2013, 03:15:27 PM
Wish I bought one when they were cheap.

Pete


Title: RE: Any market for R390A/URR?
Post by: AD4U on January 13, 2013, 03:31:45 PM
At age 64 and with almost 50 years of hamming behind me, that is the last boat anchor I want to add to my collection.  I have never even used one, but want to try.

Dick  AD4U


Title: RE: Any market for R390A/URR?
Post by: KE5YTV on January 13, 2013, 04:33:30 PM
Dick,

My 390a is clean as a pin. It is a Collins that went through a military depot refurbishment in 1986. I bought it off of Craigslist from a ham about 10 miles from my house. The problem it had was a bad cap in the IF module causing it to blow the B+ fuse. That was all it needed. I gave the fellow his asking price, $200.  ;) The deals are still out there to be had. I never thought that I would be able to afford one. Just keep watching.

73,
Mike
KE5YTV


Title: RE: Any market for R390A/URR?
Post by: KC4MOP on January 14, 2013, 03:21:51 AM
At age 64 and with almost 50 years of hamming behind me, that is the last boat anchor I want to add to my collection.  I have never even used one, but want to try.

Dick  AD4U

I don't blame you! I have one and it's nice for casual listening and AM QSO's when the bands are not full of tuner-uppers and SSB stations 1kc away from an AM QSO. The 390A is part of the Collins legacy. Still alive and working after 50 years and very mechanical. No complicated electronics...just complicated gears and cams
Fred


Title: RE: Any market for R390A/URR?
Post by: KB2FCV on January 14, 2013, 10:22:15 AM
I'd love to add one someday into the collection. One of these days I'll pick one up.


Title: RE: Any market for R390A/URR?
Post by: IW5CI on January 23, 2013, 05:34:11 AM
I love it. I use it almost every day.

http://www.youtube.com/watch?v=DpGajyWZ_vU

you can even modernize it with new earing techniques :)

http://www.youtube.com/watch?v=dISFHDISzPw


Title: RE: Any market for R390A/URR?
Post by: KD8IIC on January 24, 2013, 08:44:28 AM
 My 390A is currently with Rick Mish aka Miltronix getting a tune up. He's also doing front panel letter ingraving and refinish in semi-gloss black. I used it daily and now I miss it. Great CW, RTTY and Digital reciver. Life's too short not to have one. 73 de n8aft sk.


Title: RE: Any market for R390A/URR?
Post by: KC4MOP on January 26, 2013, 05:11:21 PM
I love it. I use it almost every day.

http://www.youtube.com/watch?v=DpGajyWZ_vU

you can even modernize it with new earing techniques :)

http://www.youtube.com/watch?v=dISFHDISzPw


The SoftRock SDR and FlexRadio software made my R390A really shine with a lot of modern bells and whistles. Really neat stuff. I never heard DRM radio reception until I see your YouTube.

Fred


Title: RE: Any market for R390A/URR?
Post by: N3DT on January 26, 2013, 07:17:01 PM
So where is the 455 to 12 converter?


Title: RE: Any market for R390A/URR?
Post by: KC4MOP on January 27, 2013, 04:18:10 AM
So where is the 455 to 12 converter?

It connects to the 455 out port on the back of the R390A. Amazing way to modernize a 50 yr old radio!!


Title: RE: Any market for R390A/URR?
Post by: N3DT on January 27, 2013, 08:33:48 AM
I kind of figured it'd be on the output of the IF strip, but where is the plan for it, like a schematic or something?  I hate re-inventing things if it's already done.


Title: RE: Any market for R390A/URR?
Post by: AC5UP on January 27, 2013, 08:43:26 AM
Mr. Google knows....................  http://users.belgacom.net/hamradio/schemas/DRM_455kHz_to_LF_Converter_FRG-100.htm (http://users.belgacom.net/hamradio/schemas/DRM_455kHz_to_LF_Converter_FRG-100.htm)


Title: RE: Any market for R390A/URR?
Post by: KC4MOP on January 27, 2013, 11:53:45 AM
soo  N3DT what converter are you interested in? AC5UP gave a link for a DRM converter, which will still need the "Sound Forge" software (FREE). 
IW5CI has a youtube showing different converters. He demos an IF converter that gives you a  software defined radio (SDR) and he shows how that same converter can receive DRM but the software for DRM is still needed to decode the interference-free, static-free audio. All of the artifacts of shortwave listening, the fading, the distortion, etc is gone. Sounds like FM radio!!!
The latest software from Flex radio  (FREE) has the filter for DRM but you still need the DRM software to decode the white noise that you will hear on the air, if tuning and listening with headphones.
The output of either the SDR (SoftRock) board or DRM module go to the sound-card input of your computer and then the magic starts ( and frustration starts) using the software to decode these signals.
info and history of SDR
http://wb5rvz.com/sdr/

I'm still wrestling with the DRM decoder software for my Flex Radio (SDR1000) and the FlexRadio software.

Fred


Title: RE: Any market for R390A/URR?
Post by: N3DT on January 28, 2013, 10:12:07 AM
Well, I guess I'll just have to make a converter.  Maybe I can find a xtal that will convert 455 down to somewhere in my SB card.  I did download Dream and fed some audio into the SB card, but I couldn't figure out how to shut off the input monitor, so I was getting the input and output monitoring at the same time, kinda confusing to say the least.  I've got some old MCL mixers that would probably work and might be easier than finding all the components to make a converter, actually I could just feed my Service Monitor into the MCL and feed the mixed output into the SB.  Hmmm.  Yeah, I'd like to hear that DRM.  I'll have to check out the Sound Forge too.

I've got the sensitivity of the R390A down to less than 1uV on most bands now.  I just need to get the AGC working better and I found a bad T202 which affects 1-3MHz, but I think I've got it working again.