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March 29th 13, 02:39 AM
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Realistic dx-300 purchase
On 3/27/13 10:47 , Kevin Alfred Strom wrote:
On 3/27/2013 11:01 AM, D. Peter Maus wrote: On 3/19/13 21:53 , m II wrote: Bought used for 90 dollars. It seems well worth it. No scratches and no corrosion in the battery compartment. Model 1A9 serial 8-0057XX. Build quality is good, but the controls are a bit on the wobbly side. Better than the tuning knob on the early Grundig Satellit 800, however. Once I got it home and practiced learning the controls it started to remind me of the FRG-7 sitting in the other room. The Barlow-Wadley tuning scheme is almost identical, with just the location of the knobs changed to protect the innocent. At first, the preselector tuning, which is a rotary knob turning a wide, frequency marked belt was frozen. A minutes of twisting back and forth has loosened it up nicely. Pure luck, no doubt. The reception is nowhere near as bad as some have reported. I tied a three foot wire to the high impedance terminal and got the 10 Mhz time signal right away. Cuba, at around 6060 Mhz (I forget the exact frequency...) came in very well also. There was no ground wire attached. The Digital readout is right on, despite the analog tuning circuitry driving it. Is anyone aware of weak points in this set? Any preventive medicine to delay an early death? As an extra bonus, the seller threw in a Patrolman 9 at no charge. He had received it in trade for a half empty bottle of Jack Daniels. It appears Holland MI is just crawling with derelict neighbours. mike The good news is, you didn't overpay. The bad news is this isn't much of a radio. DX-302 is a much better terrible radio. DX-300 is, as you've noticed, is a Wadley Loop. It's pretty stable. And, as far as sensitivity goes, it could be much, MUCH worse. Grundig's YB-500, comes to mind as an example. Audio is pretty unpleasant. A better speaker, and a bit of acoustic padding inside will take out some of the harsh resonances. Change a few coupling capacitors in the audio stage, and you can broaden the audio bandwidth, and smooth out some of the harshness. But broad bandwidth is really the issue with this radio. Selectivity is so wide, the lower sideband starts on the radio sitting next to it on the left. The 'Wide/Narrow' switch does little but drop a bypass capacitor in the audio path, taking the top off the frequency response. In the days of crowded SWBC bands, this radio could reliably receive 4 stations at once. DX-302 fixed this. Sort of. With filters. Better filters in later production runs. GRE made this radio. And it's not their best work. It's not the paperweight that many call it. That would just be insulting to paperweights. It's good for a ball game on WGN, once the audio is addressed. But if you're planning on working the bands...not exactly your most effective tool. Now, what can be done? Lots, actually. It's pretty susceptible to overload. So, keep the antenna short. 20 feet, in some areas may be too much. Work against a good earth ground. Since cold water pipes are no longer subject to the same codes as in years past, a cold water pipe may not be a reliable ground. You'll have to install a ground rod. 8' is good. 12' may be better, depending on soil moisture and height of the water table. A radio of this vintage will have capacitor problems. There will be a few, if not many, electrolytics that are out of tolerance, or failing. Replace them. Replace them all. Do it now. Do not hesitate. The radio police are looking in your windows at this moment, and if they find you've got a radio that's subpar, with bad electrolytics, they'll send you to Al Gore's house to explain to him the meaning of the words 'electricity conservation.' As bad as that is, he may also eat you. The way Mary-Chapin Carpenter ate her fan club. Or Wynonna ate an Old Country Buffet in Henderson. After replacing the caps, and you may want to replace some of the non-electrolytics, as well...especially ceramic discs in the audio stage, they have a terrifically bad sonic signature, and you will noticed the difference. Particularly on hard consonants when up on the bands. This is one of the many shortcomings of R-71, too, so you're in good company. And, you'll want to install some filters. Murata ceramics are fine. There are procedures on the web to show you what needs to be changed, and how to do it. Not tough to do, but it can be time consuming. Take at least a week's vacation. And get some rum. Bermuda is preferred. And some fresh ginger. Infuse the ginger into the rum for at least 24 hours before you begin. The more the better. It should burn all the way down. After installing filters, an alignment is a good idea. GRE radios of this vintage are not particularly good at holding an alignment. So, you'll want to make sure that the radio has come up to constant temperature before beginning. In a warm room. You may have to do this more than once over the life of the radio. It's not uncommon. Clean the switches. Replace the pots. Give the case a good cleaning. And enjoy it. After a week, put it on eBay, and buy a DX-302 with the proceeds. You'll marvel at the difference. Until someone puts you in front of a Drake.  That's the most well-written thing I've seen on this newsgroup in years. Imagine what you could write if inspired by a Racal. Or Bryce Dallas Howard. LOL! |
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