Another rig question

[WA1GFZ]

Drake sold a 6 KHz filter. I put on in my TR7A. They also made one for the 4 series.

[Steve - WB3HUZ]

That was for the C series. The low/last IF in the A/B series was LC.

[AF9J]

Thanks for the schematic with the recommended mods to the power supply Mike!! 

73,
Ellen - AF9J

The HP-23 is designed for SSB rigs but..
This is just some info on the HP-23 PS conversion when you want lower voltage, more current and more regulation on the HV. As discussed, the full wave doubler can be converted to a bridge. If you want to get fancy, add a choke as shown. Then you can get some sweet regulation for AM.

The mobile supply can be converted as well. You will go from 820 VDC at 250 mA peak to 400 VDC at a solid 300 - 400 mA. I have used this approach on Command sets in the car with modulator handled as well.

73's Mike WU2D

[AF9J]

Thanks for some of the receiver info everybody.     I used to have an R4B (and T4XC) back in the late 80s & early 90s.  I remember the widest bandwidth being 4.5 kHz. It was a good rig.  Nowadays I kind of regret selling it. There was a good point made (I'm paraphrasing) about being caught between a rock and hard place with a smaller receiver, in that you're either stuck with a very wide bandwidth, or one that's too narrow for decent audio. OK, with those thoughts in mind what would all of you recommend instead (keeping in mind I cannot afford 75A-4, or don't have space for an R-390)?  Oh, and it makes no difference to me if it's solid state, as long as it performs OK on AM.

73,
Ellen - AF9J

[W1GFH]

Thanks for some of the receiver info everybody.     I used to have an R4B (and T4XC) back in the late 80s & early 90s.  I remember the widest bandwidth being 4.5 kHz. It was a good rig.  Nowadays I kind of regret selling it. There was a good point made (I'm paraphrasing) about being caught between a rock and hard place with a smaller receiver, in that you're either stuck with a very wide bandwidth, or one that's too narrow for decent audio. OK, with those thoughts in mind what would all of you recommend instead (keeping in mind I cannot afford 75A-4, or don't have space for an R-390)?  Oh, and it makes no difference to me if it's solid state, as long as it performs OK on AM.

73,
Ellen - AF9J

My vote for the receiver of choice for the new-yet-serious AMer (as opposed to the gonzo purist who cannot tolerate anything short of an R390 or Racal) is the National NC300 or 303. Beg, borrow, steal, or contrive to get a look at one in the flesh. Very user friendly, not skittish, presumptuous, or pretentiously gimmicky. Spend a few moments getting to know this fella. Real pleasant audio. Honest tuning display. Sensitive even on 10 meters. And best of all, not a backbreaker to move.

http://www.qsl.net/ab0cw/nc303.htm

[AF9J]

Hmmmm,

I took a look at the link. It looks cool. OK, I'll put it on my list.  Thanks for the info.

73,
Ellen - AF9J

[W8EJO]

That was for the C series. The low/last IF in the A/B series was LC.

The LC filtering in the R4/A/B has a fairly gentle roll-off (4.8 KC at 6 DB down and 20 KC at 60 DB down) making the 4.8kc BW position totally acceptable for AM. I use mine for AM all the time & it sounds good to me. Not Hi-Fi but good.

Terry
W8EJO

[WA1GFZ]

A good working R390A receiver is hard to beat!

[W4EWH]

Hmmm,

[snip] Oh, BTW, I also noticed Knight T-60 on e-bay, going for $60 on e-bay.  Anybody have any thoughts on it?

[snip]

Ellen,

The T-60 and the DX-60 and the Challenger were all intended as "entry level" radios for Novice use, with some offering 6 Meter capabilities for those who upgraded to Technician.

They are basic, simple rigs, screen modulated and crystal controlled: they're easy to work on and are fine for ragchewing if the band is quiet, but you'll probably want higher power at some point.

For now, I recommend you borrow one from your Elmer or another club member, and use it until you can afford one of the "big iron" rigs: there are lots of them sitting on shelves that their owners just keep for nostalgia. You can put out the word at your local club, and there's always your friendly local BBS  .

HTH. YMMV.

73, Bill W1AC

[The Slab Bacon]

A good working R390A receiver is hard to beat!

Yea!! What he said! A good 390A Is definately tough to beat, good natured, and easy to use. I've had one (or more) for more the past 20 years! It is still the benchmark that I use to judge ALL other receivers by. 
 
                                     the Slab Bacon

[Steve - WB3HUZ]

But it's BIG, thus not meeting her requirements.

A good working R390A receiver is hard to beat!

Yea!! What he said! A good 390A Is definately tough to beat, good natured, and easy to use. I've had one (or more) for more the past 20 years! It is still the benchmark that I use to judge ALL other receivers by. 
 
                                     the Slab Bacon

[WA1GFZ]

well can I interest you in a Racal RA 6830 1/2 rack 20 LBs. not cheap though but work very well. (Shameless plug, I build them and sell one a year or so)
Or you could check out the Cubic CDR3280 on epay $4K buy it now still in production.

[Steve - WB3HUZ]

That would be an interesting dichotomy - a $4000 receiver paired with a $40 transmitter! No chance of being an alligator.

[AF9J]

VERY TRUE!

Ellen - AF9J

[W1GFH]

I'm surprised no one has mentioned the BC 348. Not too versatile, but if acquired for cheap, it can be a serviceable AM recvr.

Also of interest: the NC-270. (Often known as "Cosmic Blue" due to its striking coloration) Selectivity from 600 cycles to 5 Kc. Dimensions: 8 5/8" high---15 5/8" wide---9" deep. Shipping Weight 28 lbs.

[AB1GX]

Since we're taking about AM receivers - What's the best IF bandwidth and rolloff for AM.  The filter in my SSB rig (Swan 500) might be a bit narrow, but the phase distortion is a real killer.

If I knew what works best on AM, I'd build a active filter to AMize my rig.

Tom, AB1GX

[Steve - WB3HUZ]

There is no one best bandwidth for AM. A selection of bandwidths or continuously variable bandwidth is preferred. It all depends on the amount of QRM/band congestion. If the band is relatively uncrowded, a bandwidth 10 kHz out to 16 kHz or so are quite nice for real "hi-fi" audio. Once things get more crowded 6-9 kHz is more suitable. Under very crowded conditions or if you are working a real weak one, less than 6 kHz is often needed. Anything less than about 4 kHz really starts to kill the audio and you would be better off copying in the SSB mode.

But, if I had to go with just one, it would be 7 kHz. It's narrow enough (especially if the skirts are sharp) to kill most QRM, but wide enough to allow decent audio.

[David, K3TUE]

Oh, and it makes no difference to me if it's solid state, as long as it performs OK on AM.

Then I would put in a solid recommendation for a Drake SW-8.  It has an AM-sync detector as well.  But an external speaker will do you better, even though the internal one is not bad.

http://www.eham.net/reviews/detail/600

[David, K3TUE]

My vote for the receiver of choice for the new-yet-serious AMer (as opposed to the gonzo purist who cannot tolerate anything short of an R390 or Racal) is the National NC300 or 303. Beg, borrow, steal, or contrive to get a look at one in the flesh. Very user friendly, not skittish, presumptuous, or pretentiously gimmicky. Spend a few moments getting to know this fella. Real pleasant audio. Honest tuning display. Sensitive even on 10 meters. And best of all, not a backbreaker to move.

http://www.qsl.net/ab0cw/nc303.htm

I have done a lot of reading/asking about receivers (what to consider buying), and while I have yet to be able to operate one in person, this is one that I would suggest it is one of the most universally appreciated ham receivers.

[Pete, WA2CWA]

If you want small size and weight and great performance on AM and SSB, the Davco DR-30 is hard to beat.

[AF9J]

Now THAT looks cool!  I just did a Google on the DR-30.  It's too bad that they're so rare.  It looks very much like what I'd like to have.  BTW, the NC-270 listed above is OK too.  Also, thanks for the info on a good all around bandwidth (7 kHz - if you can't get your hands on crystal filters or other bandwidth changing devices).

73,
Ellen - AF9J

If you want small size and weight and great performance on AM and SSB, the Davco DR-30 is hard to beat.

[WQ9E]

Another possibility is something in the Heathkit SB-300 line since you do have a Heathkit transmitter.  I have a 301 and a 303 and they both do a good job on AM (I have the AM filter in both of these).  All of these models are fairly light and compact and you can choose tubes (300,301) or transistorized (303).  The Allied AX-190 (solid state Trio/Kenwood sourced) and the A-2516 (tube type and a bit less common) are also compact, light weight models.  I picked up the closely related Trio JR-310 receiver at a hamfest last year and it has the nicest tuning feel of any receiver I own (well actually a close second to the KP-81 but it weighs about 80 pounds without its matching power supply/speaker).

Rodger WQ9E

[W1GFH]

Slab Bacon has some interesting comments on the HQ-110. These are relatively lightweight and easy to hurl around the shack.

http://www.amwindow.org/tech/htm/slabrxreview.htm

[AF9J]

Hi Joe & Roger,

The Trio JR-310 - I took a look at it on the Rigpix website.  It looks similar to a TS-520S I birefly owned in college in 1986.  I can believe that it's tuning feel is good.  I have a TS-820 (the very first year edition of the 820 series [mine has just the analog dial display, since the digital display was only avialable as an option, when it was made in 1976]), and it has a fantastic, silky smooth feel to its tuning.  What's the bandwidth of it, in AM mode?

The HQ-110 - I had one back in 1995, when I made my brief foray into AM  back then (want to get cheased off of AM? - live in an area that has Channel 2, and marginal reception of it at best.  can you say TVI issues in the making? sure you can, I knew you could!).  It's an OK receiver in its stock form. I agree with Slab Bacon that the mods that can be made to it, make it much better. But nevertheless, in stock form, it is, in my personal experience, a pretty useable receiver for AM.

All of you are great!!  Thanks so much for the info and suggestions. They sure beat me having to reinvent the wheel, and find out the hard way!

73,
Ellen - AF9J

[The Slab Bacon]

Speaking of my "receiver road test" article, as soon as I get a chance to type it up and send it to Steve, I have 5 or 6 more receivers to add to it. (hamfesting has been good to me the last 2 years)
                                            the Slab Bacon