Online Business, Antenna, Coax & Connector FAQ Page

Below you'll find a short FAQ that has been created for the purpose of trying to anticipate some of the more common questions people may have, regarding DPDP products. If you can't find an answer to your question here, please email us at: dave@dpdproductions.com

PLEASE READ: Due to the complexities of offering oddly sized products, this site only calculates shipping for US destinations. If you'd like to ship outside the US, please contact us and we will email you an invoice for your order, which you can then pay electronically.



FAQ List

General FAQ

Q: Do I have to use PayPal to make payment?
Q: Why won't the shopping cart system work for me?
Q: How are orders shipped?
Q: How long will it take to receive my order?
Q: Can I get something custom built?
Q: Do you make foreign sales, and how is shipping handled?
Q: Where are DPDP products made?
Q: Are any of your products available in stores?
Q: How do you handle returns?
Q: How can I make a custom order or order multiple items?

Antenna FAQ

Q: What makes one antenna better than another?
Q: Why do you say the LP is better than a discone?
Q: Can the outdoor models be used inside?
Q: Can the indoor 'Blade' models be used outside?
Q: Will I be able to hear stuff other than what the antenna was designed for?
Q: How well will I be able to receive stuff?
Q: I've seen other antennas for less money. What about those?
Q: Will I only hear things in one direction on the LP directional antennas?
Q: Do I have to have a rotator to use one of the LP antennas?
Q: Why can't I mount the LP antenna horizontally?
Q: I heard the railroads are changing to digital... Will I be able to listen still?
Q: Where can I get the hardware needed to mount an antenna on the roof?

Coax Cable FAQ

Q: What kind of cable do I need for my outdoor antenna?
Q: How does cable signal loss affect performance?
Q: Will I have loss using a small cable for a short length on a longer big cable?
Q: What are the basic cable sizes?
Q: So what exact cable choices do I have?
Q: That's all great, but what do you recommend for the average setup?
Q: What about cables like RG6 and RG59?
Q: What's with all the different connector types?
Q: So what connectors do I need to use on DPD Productions antennas?
Q: How does it work if I want to use a rotator?
Q: I can't make cables, so who could do it for me?
Q: What cable can I use on my SBS-1 / RadarBox?


General FAQ


Q: Do I have to use PayPal to make payment?
A: No, you do not... PayPal is simply the payment processor. Once you add your items to your cart, you can go to check out and pay using your PayPal account... OR, pay as a 'guest' using any major card. PayPal does NOT require people to have an account to pay.


Q: Why won't the shopping cart system work for me?
A: Make sure you're running the latest version of your browser. Also make sure you have Java turned on in the browser preferences, as well as have it set to accept cookies. If you still have problems, please email us.


Q: How are orders shipped?
A: Usually by USPS Priority to US destinations. Foreign orders may be shipped in various ways, depending on the destination. Please email us for a foreign shipping quote. Don't forget to include your city and postal code.


Q: How long will it take to receive my order?
A: Every attempt is made to get orders out as soon as possible. However, we are a small company, and as such, we aren't always able to do the instant 24/7 type of shipping that many larger companies can. On occasion we will have a run on a particular item, and that item will become backordered, or have a short waiting period before it goes out. If that's the case, a note will be posted for that product on the web site. Once products are shipped they usually take about one week to arrive at US destinations. This does not include holidays or weekends. It also takes longer for foreign shipments, depending on the destination.


Q: Can I get something custom built?
A: It all depends... If the product you'd like falls within the basic design of what we already offer, it may be possible to create what you're looking for. Details of what you need should be sent by email to us so we can talk about it further. All efforts will be made to fill a custom order, if at all possible.


Q: Do you make foreign sales, and how is shipping handled?
A: We try to sell outside the US, but it's necessary to contact us regarding that, as it all depends on the country. Shipping can often be an issue with parcels that are deemed 'over-sized' by shippers. Most of the time it can be done. We ship our products all over the world, with very few problems... and it's really not that expensive. So don't be shy about trying it.


Q: Where are DPDP products made?
A: All DPDP base antenna products are made right here in the US by us. And when we say "made", we don't mean simply designed by us, then out-sourced for manufacturing in China or some other country... We mean that they're physically made here, by us. Some mobile product components do come from other sources, but some also come from the US.


Q: Are any of your products available in stores?
A: Not at this time... All DPDP products are sold directly through this web site, in an effort to try and keep costs as low as possible.


Q: How do you handle returns?
A: Due to the nature of the products, merchandise is considered to be in a 'used' condition as soon as it is installed. Therefore we typically cannot accept returns based purely on whether the customer simply likes something or not. Being a small business, we cannot afford to have products "tried out", because the product can no longer be sold as new once it has been used. However, we will work with the customer to try and do everything we can to offer support and bring satisfaction. If for some reason the product is defective and a part cannot be sent to repair the product, we will then accept the product as a return to fix or replace. The customer is ultimately responsible for any damage incurred during installation. Unauthorized returns will NOT be accepted, and returned to the sender.


Q: How can I make a custom order or order numerous items?
A: Due to the nature of this business, there can be an almost infinite amount of options when it comes to ordering a product. Antenna type, cable type, connector type, shipping, and many other things, all have to be taken into consideration. For this reason, it's sometimes easier to just take multiple item or custom orders, on a case by case basis. Also, sometimes it just helps to first hear what a customer is trying to accomplish. Oftentimes we can help you decide what would work best in your situation. Please email us with what you're looking for and we can give you a quote, then send a payment request to you for the order.


Antenna FAQ


Q: What makes one antenna better than another?
A: There's two basic things that determine how well an antenna will perform... The amount of elements it has (not including ground plane or duplicate elements), and how closely it's tuned to the frequency you are trying to hear. That's it! It doesn't matter how fancy something looks, or what the claims are. Every time you add an element, you increase gain, and the smaller the amount of bandwidth an antenna try's to cover, the better it will perform. Saying something is "25-1300 full coverage" means nothing when it comes to performance... An antenna designed to cover one portion of a band, will perform better than one trying to cover everything. An antenna that has multiple stacked elements (horizontally or vertically) will perform better than any single element antenna. Any type of ground plane antenna is basically zero gain. Same goes for a discone. A dipole is slightly better, but still the same when compared to each other. Those are all basically single element antennas. If you want more performance, you have to use antennas that have stacked elements, and also focus on the band/frequency you are operating on. Yes, this means the antenna can be fairly big. It also means you may have to use a directional antenna. Typically a directional antenna is the only way you will be able to attempt maximum performance. This is why the traditional TV antenna has always looked the way it has. It is physically impossible for an antenna to perform really well, cover all bands, be 100% omni-directional, AND be small. Unfortunately, nature just doesn't work that way. When looking for a good basic antenna, don't fall for gimmicks... Look for quality. You may think you're saving a lot of money by going with a $19.95 special, but if it falls apart after a year, then it's not such a great deal.


Q: Why do you say the LP is better than a discone?
A: A typical ground plane or discone is basically 0 gain or worse. There's a common misconception that a directional antenna will only receive signals in the direction it is pointed, which is why many people think they need a discone for 'wide-band' omni performance. True, directional antennas *can* be fairly deaf to the sides and back, but they can also be designed not to be. The DPD Productions LP antennas are designed to have fairly good reception to the sides and back. This means you're still getting 360 degree coverage with the LP. Plus, you get the added gain in the direction the antenna is pointed. The common misconception of: "I don't want a directional antenna because I won't be able to hear stuff all around me" is not really true.


Q: Can the outdoor models be used inside?
A: Yes, but they were designed to be used outside. If you're an apartment or condominium dweller, you may want to consider an indoor model. You could possibly mount an outdoor model in the attic though, or on a balcony.


Q: Can the indoor Blade models be used outside?
A: If there's a protected spot outside where it will not come directly in contact with the elements, you could probably leave it there for fairly long periods without any problem. The antenna was designed for indoor use though.


Q: Will I be able to hear stuff other than what the antenna was designed for?
A: Yes... All antennas are capable of hearing bands other than the one they were designed for... That's why advertising an antenna as being 25 to 1300 MHz "full coverage", really isn't any great thing. It's just a matter of *how well* an antenna will receive multiple bands. Contrary to what many manufacturers would have you believe, there is no such thing as an antenna that has a high level of performance along a very wide bandwidth (ie: 25 - 1300 MHz). Every antenna has high points of resonance, and low points of resonance. Typically, the wider an antenna is in bandwidth, the lower the performance will be on any single band. That's why having antennas designed for specific bands is always best. But even using antennas designed for a specific band will typically still allow you to hear other nearby bands. A good thing to do is decide what band you need improved reception on most, and what bands come in fairly well no matter what. If you live in a large city, the 800-900 bands usually come in fairly well. Simplex type communications on VHF are often more difficult to receive. In that instance, having a dedicated VHF antenna would probably be good, since you would get the best performance on VHF, but still be able to hear the UHF signals.


Q: How well will I be able to receive stuff?
A: This question is almost impossible to answer. It depends on how close you are to the transmissions, your elevation, the topography, and many other things.


Q: I've seen other antennas for less money. What about those?
A: No doubt, there are less expensive antennas out there. But if you compare features and parts, you'll find in most cases that the cheap antennas being offered by other companies don't compare. For instance... Our Blade Indoor Models include RG8/X cable... Most companies include off brand RG58 cable, if any cable at all. Our Outdoor Vertical Models include an N connector... Most companies use the cheaper, less weather resistant UHF connector. All the DPDP outdoor models include mounting hardware... That's extra on many other people's antennas. The simple fact is that most $20-30 antennas you see advertised, won't even make it through a decent winter. The majority of these types of products are produced by large corporations that have everything made overseas by cheap foreign labor. It's virtually impossible to make a quality product in the US, using US citizens, and still be able to charge competitively low prices. Often people who own $5000 or more of radios say they don't want to spend more than $50 on an antenna. In radio, you have to take the whole system into consideration... Any system is only as good as its weakest link. Yes, radios are more fun to spend money on... but a good antenna and cable is just as important. Plus, if you have to replace a cheap antenna every other year, it's not such a great deal in the end.


Q: Will I only hear things in one direction on the LP directional antennas?
A: No! The LP antennas don't function as if you are hearing things through a tube from just one direction. You will still hear signals from all directions, often-times as good as a basic omni type antenna would. The LP antennas just hear signals best in the direction they are pointed. This type of antenna can be designed numerous ways... In the design process, you have a choice of making an antenna that is very directional, or one that is directional, but still has decent omni ability... The DPDP LPs were designed to have respectable omni ability, as well as improved performance directionally.


Q: Do I have to have a rotator to use one of the LP antennas?
A: Absolutely not... A rotator can help if you want to turn the antenna to hear best in the direction a certain signal is coming from. Otherwise, you can mount the antenna in the direction you are most interested in, and you'll still get decent reception from other directions.


Q: Why can't I mount the LP antenna horizontally?
A: Configuring the antenna to be horizontal would be counter-productive. Virtually all the signals you want to hear are typically polarized vertically. Using an antenna that has opposite polarization from the one that is transmitting, will usually lower the performance quite a bit.


Q: I heard the railroads are changing to digital... Will I be able to listen still?
A: Yes! There is about a 90% chance you will still be able to listen. But this is a very slow process (as in years)... So don't worry. Check out this page for more info on the railroad band restructuring.


Q: Where can I get the hardware needed to mount an antenna on the roof?
A: Believe it or not, good old RadioShack is still good for something. It depends on the store, but they often stock standard 1 1/4" mast and various hardware to mount on the side of a structure or roof. Home centers like Lowes sometimes have stuff in the TV section also. Typically you don't want to use a 1 1/4" mast higher than 10' without using guy wires.


Coax Cable FAQ


Q: What kind of cable do I need for my outdoor antenna?
A: Basically speaking, you need a 50 Ohm coaxial type cable, or what's commonly referred to as 'coax'. This type of cable comes in numerous sizes and brands. The larger (thicker) the cable is, the less signal loss you will have on long lengths.


Q: How does cable signal loss affect performance?
A: The longer a cable is, the more signal loss you have as it flows through the cable. This effect becomes more pronounced as the frequency you're using goes higher. For instance... If you had 50' of cable, there would be more loss while operating at 900 MHz than there would be at say, 40 MHz. Typically losses for a cable are listed at different frequencies, based on a 100' length. As an example... A 100' piece of LMR400 has a loss of 1.5 dB at 150 MHz and a loss of 4.0 dB at 1000 MHz. As far as real world performance is concerned, you really aren't going to start noticing a difference until it's at least 2 dB and higher.


Q: Will I have loss using a small cable for a short length on a longer big cable?
A: No... This is a common misconception. Signals don't move through cable the same way water moves through a tube... You don't get a blockage at one point by using a smaller cable. Say for instance you have 100' of LMR400 cable, and then you use 3' of RG58 for a flexible patch cable at the end... Only 3' of the small cable isn't going to change anything, because even at 1000 MHz, that would only come out to about .49 dB of loss. Yes, that's something, but you would never actually hear it. Now if you ran the whole length with RG58, then that would be bad.


Q: What are the basic cable sizes?
A: In the US, the two designations you see the most for cable sizes are 'RG' and 'LMR'. The 'RG' designation is used across numerous brands, whereas the 'LMR' designation relates to the Times Microwave brand of cables. The actual physical dimensions for RG and LMR sizes can often be the same, but sometimes there are slight differences. The way they try and make this easier to understand is that the industry assigns a "Cable Group" letter to both cables and connectors. For instance... Times Microwave LMR400 and Belden 9913 are both considered "Group I"... They're both technically an RG8 size cable that physically have the same overall outer diameter and center conductor diameter. So in this case, the same connector would work on both.


Q: So what exact cable choices do I have?
A: See the chart below... These are some of the most common cable choices available for typical communications applications. All are 50 Ohm and tend to be listed from lowest loss (top) to highest loss (bottom), but not in exact order. Check manufacturer specs for the exact loss numbers for each band, on each cable.

Coax Cable Guide
Size
Model
Maker
Group
Center
Notes
1/2"
LDF4-50A
Andrew Heliax
L1
Single
This cable is moving into commercial/broadcast grade. It's very stiff and difficult to work with.
5/8"
LMR600
Times Microwave
L2
Single
Very stiff. This cable would need a smaller patch with anything less than the biggest desktop radio.
5/8"
LMR600UF
Times Microwave
L2
Multi Strand
More flexible than the single conductor version above, but still big and difficult to work with.
1/2"
LMR500
Times Microwave
L1
Single
Very stiff cable and will most likely need a smaller patch to work with anything but the largest radios.
RG8
9913
Belden
i
Single
9913 has been around a long time, but sometimes water seepage can be more of a problem on this cable.
RG8
9913F7
Belden
i
Multi Strand
This is the more flexible version of regular 9913. This can be easier to work with.
RG8
9914F
i
Multi Strand
Known as "Bury-Flex". This cable is a very good all around cable and fairly easy to work with. It's flexible enough to be used with rotators and can often go directly to radios without a smaller patch.
RG8
LMR400
Times Microwave
i
Single
400 is an all around good cable. It doesn't seem to exhibit water problems as much as 9913, but it's still pretty stiff and can be difficult to connect directly to smaller radios without a patch cable.
RG8
LMR400UF
Times Microwave
i
Multi Strand
'UF' stands for "UltraFlex". This cable is more flexible and easier to work with than the regular 400.
RG8
Flexi-4XL
i
Multi Strand
This is another multi strand flexible RG8 cable that www.thewireman.com offers.
RG8
Super 8
i
Multi Strand
Slightly more loss than the Flexi-4XL, but also flexible to work with.
RG213
Various
Various
e
Multi Strand
More popular in Europe than the US. Typically has a 7 strand center conductor. Somewhere between RG8 and RG8X in terms of loss. Harder to find connectors in the US. Better to just go with RG8.
RG8X
LMR240
Times Microwave
x
Single
Same outer dimension as regular RG8X, but slightly less loss due to solid center conductor. Too stiff to use in most mobile applications.
RG8X
LMR240UF
Times Microwave
x
Multi Strand
'UF' stands for "UltraFlex". Basically the same as regular RG8X. More flexible than regular LMR240.
RG8X
"Mini 8"
Various
x
Multi Strand
RG8X size cable is offered under numerous brands. The 'RG8' designation is misleading, because it's considerably smaller than RG8 size cable. RG8X is good for runs shorter than 25', patch cables, and mobile applications.
RG58
LMR200
Times Microwave
c2
Single
Same outer dimension as normal RG58 cables, but center conductor is slightly larger, so it often won't fit in normal RG58 connector pins.
RG58
Various
Various
c
Both
RG58 comes in both single conductor and multi strand variety, and many different versions. Bottom line, this should only be used in mobile applications or in very short runs.


Q: That's all great, but what do you recommend for the average setup?
A: We like to recommend Davis RF 9914F "Bury-Flex" as an all-around good cable for any run longer than 40'. It's a very durable cable and can be put underground as well. It has a loss rate very similar to LMR400, but its multi strand center conductor makes it much easier to work with... The cable is flexible enough to attach directly to many smaller radios without using a smaller patch cable, and can be used directly on rotators. Flexibility is good to have, because it allows you to do things without using patch cables, which means less connectors/adapters and less things to break. It can also be used directly on SBS-1/ RadarBoxes as long as you provide some physical support for both the cable and box (though it looks kind of silly). If you're going 40' or shorter, you can usually get away with RG8X size cable, though that could still give a noticeable loss with higher bands like 800-1000 MHz. But for VHF it would be fine.


Q: What about cables like RG6 and RG59?
A: RG6 and RG59 are 75 Ohm cables that are primarily designed for TV work. Yes, many people have used RG6 for receive purposes and it can work OK, but it's not the proper cable to use in communication applications... You'll probably have to use adapters to do so, which is never a good idea. Most comm equipment is designed to be used in 50 Ohm systems. Some manufacturers offer RG6 cable with their antennas, simply because it's more plentiful and cheaper.


Q: What's with all the different connector types?
A: Yes, there's many different types of connectors. Forget about 'F' connectors, because those are for RG6 and that cable shouldn't be used for communications. Same goes for RG59 & 60 connectors. Many of these come in a 'crimp' style and 'clamp' style, and are available for most popular cable sizes. Crimp style is less water resistant on exterior connections, but it can be physically stronger on the cable. Clamp style has a small rubber gasket which helps keep water out of the cable, but it can be a physically weaker connection to the cable. Some of these connectors can be available in both 50 Ohm and 75 Ohm. 50 is what's needed in communication applications.

Connector Guide
N

Male

Female

This is the most common connector used in proper interior/exterior communication applications. They're more water resistant than UHF connectors in the clamp versions, and they also handle higher frequencies better. They come in both crimp and clamp form, clamp being the more water resistant, crimp being attached to the cable in a stronger fashion.

UHF

Male

Female
The UHF connector is the most common connector found on consumer grade equipment for both interior and exterior, but it's not the best connector to use. It can usually handle higher power than N connectors can, but it's much worse at handling higher frequencies, and is less water resistant. The UHF connector became a tradition by default because of it's age... which makes them cheap, and that's why they continue to be used. The Male UHF is technically referred to as a PL259 and the Female is referred to as an SO239.
BNC

Male

Female
BNC is probably the most popular quick -disconnect type of connectors used for interior applications. They're referred to as Male or Female. BNC is found on most scanners and many handheld ham radios. They're primarily used for indoor applications. They also make good connectors for patch cables.
TNC

Male

Female
The TNC connector isn't terribly popular, but it does get used once in a while. TNC connectors are basically a threaded version of the BNC. They also work better at higher frequencies, making them good for patch cables used in critical applications. Typically they would be seen on more commercial grade equipment.
Mini UHF

Male

Female
Mini UHF connectors are exactly what the name implies... a smaller version of the large UHF connector. Mini UHF connectors occasionally show up on equipment, but aren't used much. Like the larger version, they aren't very good with high frequencies.
SMA

Male

Female
SMA stands for: "Sub Miniature Version A". The SMA connector is the most diverse and sometimes confusing connector there is. The SMA was created for applications where space on the device is an issue. The SMA has good performance but is very small, which can often make it a physically weak connection. You wouldn't want to use SMA unless a device dictates it. What makes it confusing is how manufactures use it... Typically it will be used on small handheld devices. Sometimes they will use a 'Reverse Polarity' version, where the outer chassis or inner pin sex is reversed. Also, manufacturers will sometimes put the Female version on the radio and other times the Male version... This sometimes comes down to the design, but they also do it to try and create a proprietary connection so you'll have to buy their own antennas and accessories.
Motorola

Male
Motorola connectors aren't really used on scanners or consumer equipment much anymore, but they use to be used on older equipment, including scanners. These connectors kind of look like an RCA audio connector, like you see on TVs and stereos. Adapters can often be found to use them with BNC connectors.
F

Male

Female
F connectors are primarily for 75 Ohm video applications, and should not be used in radio applications if at all possible. That said, there are some manufacturers that offer RG6 cable and F connectors with their antennas. This is mainly done because RG6 cable is cheap and plentiful.
Reverse
Polarity

BNC Male RP

SMA Female RP

TNC Male RP
In rare instances you might run into a version of a connector that is referred to as "Reverse Polarity". These connectors will either have outer threads that are the reverse of what would normally be used on the same connector, or inner pins that are the opposite sex of what would normally be used on the same connector. Notice in the photos above how each pin is actually the opposite of what would normally be used. These have started popping up more and more, mainly because the FCC believes this will hinder people from using illegal external antennas that are not supposed to be used on certain equipment. But you can also find reverse polarity connectors on some equipment from manufacturers who are trying to get people to buy their own antennas.


Q: So what connectors do I need to use on DPD Productions antennas?
A: All of our outdoor antennas use 'N' Female connectors. So you would need a Male 'N' on the antenna end of your cable for those. If you already have cable with UHF connectors on it, we don't recommend them, but we can put a Female UHF connector on the antenna for you. Our interior Blade model antennas and mobile antennas often come with a Male BNC connector, but we can also put other types on if you need it. Sometimes we can also figure out ways to hook things up to more odd equipment, like older Motorola "Universal" connections and other things.


Q: How does it work if I want to use a rotator?
A: You either have to use one main cable that is flexible enough to be rotator safe, or use a separate cable up at the rotator that is more flexible. The easiest way to do it, is use a multi strand flexible cable like Davis RF's "Bury-Flex". Then you just leave enough slack up near the top by the rotator so that when it spins all the way around 360 degrees, it will be lose enough to bend.


Q: I can't make cables, so who could do it for me?
A: Davis RF is a good company to contact. They can use the cable you prefer and put the connectors you want on it for a fee.


Q: What cable can I use on my ADS-B Box?
A: The SBS-1 uses a BNC connector. The SBS-1e and RadarBox use an SMA connector. Some of the new little USB receivers use an MCX connector. You will need to use an adapter for MCX, because MCX was never intended to be used with standard 50 Ohm cables. Because the ADS-B system operates up at 1090 MHz, loss can be a real issue with cable. Using a low quality cable could really degrade the signal coming into your receiver. We recommend a full RG8 size cable for anything longer than 30'. If you want to use a single center conductor cable, it's going to be very stiff and difficult to work with. If you choose a flexi style cable with a multi strand center conductor, it will make it easier. SMA connectors are very small, but people have reported successfully using an SMA on an RG8 size cable, and directly connecting it to the box. But it's very important to reinforce both the cable and box by using velcro or something, to hold them both down on the table. We also offer flexible patch cables as an option, with our ADS-B outdoor antenna.


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