Old rigs never die 3
This content first published at V44KF.spaces.live.com on 30th September 2008
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Last week I finally acknowledged the fact that 'old rigs never die' ... but they can most certainly be killed by their owners through a lack of knowledge. The resurrection of old rigs can come with a cost but it is my preferred option. From 'old rigs never die 2' posted here on 27 April 2008, I made two observations. [a] The ham rigs with the best receiver specifications were made in the USA and [b] more than half of the ham rigs with performance figures above the minimum specification for the standard ham radio receiver, were manufactured before 2004, and were no longer in production. So it is a fact that more than half of the top ham radio receivers that meet today's high quality receiver specifications are old rigs, with most of them dating past 7 years.
Among the many things that hams are good at, it is telling the ham equipment manufacturers how to improve the performance of their ham gear, after the fact, with circuit updates called modifications. These updates fix and repair the 'engineering design discrepancies', that affect proper operation of the equipment. At the end of day the ham operator has a much better than 'off the line' ham radio product. Most modifications are pretty simple, from changing components to substituting new values, which can be performed by the ham operator, with a little technical ability. But that was once ago, because I understand that in the modern rigs of the last few years, with surface mount technology, the average ham could be out of his league. But getting the appropriate technical assistance is not usually a problem. The old rigs still provide a means of hands on for those of us who still want to feel modern around an ESD pencil soldering iron and solder sucker.
Modifying the old rigs can greatly improve their performance/specifications, sometimes to the point where they could exceed the performance/specifications of other models that are in a higher price bracket. The price tag on any ham radio receiver out of the box is determined, among other things, by [a] the selectivity and [b] the frequency stability. These two parameters are what separate the $10K rigs from the $1K rigs. Or maybe more correctly, these parameters are what seem to determine the price tag. Of course these days the Japanese add a host of bells, whistles and lights, probably to justify the top of the line price. But when you look at the top of the line gear of yesteryear from the same Japanese maker you have to wonder what happened, because sometimes the older gear outperforms the newer ones. Older ham equipment was not made with upgrades in view, but some ham gear is more amenable to modification, and I have personal knowledge of and experience with the Kenwood brand of ham radio equipment. But then you only have to peruse the modification implementation methodology and draw your conclusions.
For the purposes of our ham radio hobby selectivity and frequency stability does not play an extremely critical role, and the out of the box radio is what most of us require. But when you live in kilowatt alley or on an island where hams live within 300 meters of each other, you may have to seriously think about the selectivity of your receiver. But this is only necessary if your ham neighbor will be operating less than 10KHz away from your frequency, and both of you are chasing DX at the same time or working in a contest. To operate interference free you have two options. First, you can get the top of the line receiver with all the bells, whistles, lights and stuff which will work superbly out of the box. Secondly, you can get a not so modern receiver and install INRAD filters for improved selectivity. For low band operating and DXing selectivity may become an issue for some hams. Otherwise than that selectivity is not usually an issue. And frequency stability does not factor into any ham hobby operation at all. Radios with 30PPM are coexisting with radios of 0.5PPM and everybody is happy.
But there is more to the ham radio hobby than just chatting to one another. Our hams are prepared to give service in emergency situations. It is necessary that we know what level of service we can give. This is determined for the most part by the ham radio equipment that we will be using to interface with internal and external agencies. This sounds simple enough but when you drill down to the roots you will discover that the agency you must interface with require that your equipment is compliant with a technology standard to ensure that our equipment can sync up with the external radio network. If for example we have to establish a a communications link/interface to a "warship" or an "aircraft", in the course of an emergency operation, will we be able to conduct efficient and reliable communication? Yes we can, if our hardware is compatible through compliance.
The agency or institution that our transmission equipment will interface with during an emergency operation will be using commercial grade equipment that is compliant with the NTIA specifications. Ham radio gear is not usually built to that specification, so only one or two pieces of ham radio equipment off the shelf can interface with the commercial communication system. The one parameter where almost all ham equipment falls short is frequency stability. The NTIA requirement is better than 0.67PPM for +/- 20Hz. The $10K+ rigs meets this requirement. Most rigs with their TCXO options could meet this requirement, but unfortunately most of these options are no longer available over the counter. But all is not lost because hams can fabricate their our TCXO options to meet or better the NTIA spec.
Armed with the above information I am now working to make my old rig NTIA compliant. That will put it in the league [frequency stability wise] with rigs costing $10K uncle Sam. And all that I need is a $150 TCXO, a soldering iron and a little time.
[To be continued]
*******************************************
Last week I finally acknowledged the fact that 'old rigs never die' ... but they can most certainly be killed by their owners through a lack of knowledge. The resurrection of old rigs can come with a cost but it is my preferred option. From 'old rigs never die 2' posted here on 27 April 2008, I made two observations. [a] The ham rigs with the best receiver specifications were made in the USA and [b] more than half of the ham rigs with performance figures above the minimum specification for the standard ham radio receiver, were manufactured before 2004, and were no longer in production. So it is a fact that more than half of the top ham radio receivers that meet today's high quality receiver specifications are old rigs, with most of them dating past 7 years.
Among the many things that hams are good at, it is telling the ham equipment manufacturers how to improve the performance of their ham gear, after the fact, with circuit updates called modifications. These updates fix and repair the 'engineering design discrepancies', that affect proper operation of the equipment. At the end of day the ham operator has a much better than 'off the line' ham radio product. Most modifications are pretty simple, from changing components to substituting new values, which can be performed by the ham operator, with a little technical ability. But that was once ago, because I understand that in the modern rigs of the last few years, with surface mount technology, the average ham could be out of his league. But getting the appropriate technical assistance is not usually a problem. The old rigs still provide a means of hands on for those of us who still want to feel modern around an ESD pencil soldering iron and solder sucker.
Modifying the old rigs can greatly improve their performance/specifications, sometimes to the point where they could exceed the performance/specifications of other models that are in a higher price bracket. The price tag on any ham radio receiver out of the box is determined, among other things, by [a] the selectivity and [b] the frequency stability. These two parameters are what separate the $10K rigs from the $1K rigs. Or maybe more correctly, these parameters are what seem to determine the price tag. Of course these days the Japanese add a host of bells, whistles and lights, probably to justify the top of the line price. But when you look at the top of the line gear of yesteryear from the same Japanese maker you have to wonder what happened, because sometimes the older gear outperforms the newer ones. Older ham equipment was not made with upgrades in view, but some ham gear is more amenable to modification, and I have personal knowledge of and experience with the Kenwood brand of ham radio equipment. But then you only have to peruse the modification implementation methodology and draw your conclusions.
For the purposes of our ham radio hobby selectivity and frequency stability does not play an extremely critical role, and the out of the box radio is what most of us require. But when you live in kilowatt alley or on an island where hams live within 300 meters of each other, you may have to seriously think about the selectivity of your receiver. But this is only necessary if your ham neighbor will be operating less than 10KHz away from your frequency, and both of you are chasing DX at the same time or working in a contest. To operate interference free you have two options. First, you can get the top of the line receiver with all the bells, whistles, lights and stuff which will work superbly out of the box. Secondly, you can get a not so modern receiver and install INRAD filters for improved selectivity. For low band operating and DXing selectivity may become an issue for some hams. Otherwise than that selectivity is not usually an issue. And frequency stability does not factor into any ham hobby operation at all. Radios with 30PPM are coexisting with radios of 0.5PPM and everybody is happy.
But there is more to the ham radio hobby than just chatting to one another. Our hams are prepared to give service in emergency situations. It is necessary that we know what level of service we can give. This is determined for the most part by the ham radio equipment that we will be using to interface with internal and external agencies. This sounds simple enough but when you drill down to the roots you will discover that the agency you must interface with require that your equipment is compliant with a technology standard to ensure that our equipment can sync up with the external radio network. If for example we have to establish a a communications link/interface to a "warship" or an "aircraft", in the course of an emergency operation, will we be able to conduct efficient and reliable communication? Yes we can, if our hardware is compatible through compliance.
The agency or institution that our transmission equipment will interface with during an emergency operation will be using commercial grade equipment that is compliant with the NTIA specifications. Ham radio gear is not usually built to that specification, so only one or two pieces of ham radio equipment off the shelf can interface with the commercial communication system. The one parameter where almost all ham equipment falls short is frequency stability. The NTIA requirement is better than 0.67PPM for +/- 20Hz. The $10K+ rigs meets this requirement. Most rigs with their TCXO options could meet this requirement, but unfortunately most of these options are no longer available over the counter. But all is not lost because hams can fabricate their our TCXO options to meet or better the NTIA spec.
Armed with the above information I am now working to make my old rig NTIA compliant. That will put it in the league [frequency stability wise] with rigs costing $10K uncle Sam. And all that I need is a $150 TCXO, a soldering iron and a little time.
[To be continued]
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